Help me understand which camera memory card to buy, and also (potentially) where I might buy one in Boston/Cambridge (or online)!

I pretty much use http://www.amazon.com/exec/obidos/ASIN/B000PO3CTM/metafilter-20/ref=nosim/ for everything. They're cheap, work great, and I haven't had one go bad on me yet.

I will want to take a lot of pictures Get more than one.

I have two memory cards, which I use for both museums objects/site research and for personal use. They're both SanDisk; one's 8GB and the other is 4GB. Your camera should take a standard card of the sort that Amazon suggests for you. I've had one of my cards for years and taken probably 5-6000 pictures on it without a problem. I really suggest buying two cards and an additional charged battery; I like being able to have the extra time and space if I need it, but also so that if I have Absolutely Irreplaceable photographs I can put that card (in a little plastic holder) safely away and use the other one in the meantime. At any rate, they're very common and easy to use, as long as you're careful in taking them in and out of the camera. More important for your research would probably be figuring out the size and quality of the pictures themselves you want when taking them. If you haven't tested it out yet in a variety of settings and light conditions, you might find that useful and reassuring (it will also give you a chance to test out your new memory card.) You also may want to test out inexpensive tripod mounts like the Gorillapods if you are working with documents in low light conditions. Good luck!

Your camera supports SDHC (your camera http://service.us.panasonic.com/OPERMANPDF/DMCLS75.PDF in pdf format). SDHC cards come in different speed classes, which are the numbers of MB/sec that can be written to the card. For your purposes, class 4 should be fine. The class is designated on the card by a number inside a circle with a small opening on the right. On this camera, with a 4GB card at the best quality, you're going to get 1000 images. I wouldn't be comfortable keeping that many on one card, so if you're going on a long vacation, or won't be downloading often, get at least 2 cards. I've used http://www.amazon.com/exec/obidos/ASIN/B000VUVA62/metafilter-20/ref=nosim/ and http://www.amazon.com/exec/obidos/ASIN/B000OF2F36/metafilter-20/ref=nosim/ class 4's and found them both reliable. It looks like the difference to 8GB isn't that great in price, in fact the SanDisk is cheaper, so you might as well go for that. If you ever plan to get a different camera and shoot more video, you may also consider getting a class 10 now. I currently use the 32GB version of this http://www.amazon.com/exec/obidos/ASIN/B003VNKNEG/metafilter-20/ref=nosim/ card and have had no issues with it.

The cheap ones that they have at the checkout counter at Microcenter on Memorial Drive in Cambirdge will do the trick. I've been using them for years in phones, tablets, camera, & Open Pandora. I've only had one fail. Don't buy one off ebay. A lot of sellers (not all) are selling some under brand names when they are probably lower quality than the ones at Microcenter. Also, check out http://www.slickdeals.net.net for any current deals on cards.

http://www.dpreview.com/news/2007/1/31/panasonicls75ls60 says your camera uses SD and SDHC cards. It also comes with a small amount of internal storage (27MB) so you could actually use it w/o a memory card although 27MB holds only a dozen or so photos at the largest image size your camera is capable of shooting. SD and SDHC cards are the ones the size/proportion of a "Forever" postage stamp. SanDisk is good. I usually buy the same ones sanka has linked above. IMO, it's somewhat better to have multiple smaller capacity cards than one big card (where big = 32GB and up) because if you get behind in transferring the data off the cards and one goes bad*, at least with the smaller cards you only lose some data rather than all of it. Regarding avoiding 3rd party vendors on Amazon, on the item's page look under "In Stock" (right below the price) and stick to ones that state "Sold by Amazon" or "Fulfilled by Amazon." Either means your stuff is coming from an Amazon warehouse and should be eligible for Prime. Tips: make sure your camera is turned off before you remove or insert the memory card. Don't touch the gold contacts of the memory card while handling it. When the memory card is out of the camera, protect the gold contacts from getting scratched by putting the card back into the little plastic case it came with when you bought it. If the software interface on your Lumix is anything like the one on my Lumix (great P&S cameras, btw), after you insert a card and power up the camera will display a brief message with words to the effect of "using memory card." Another tip: set your camera to shoot the largest size possible because you cannot size digital photos up in size gracefully but you can always size them down and hey, storage is cheap. You might want to consider getting a http://www.amazon.com/IOGEAR-Pocket-Memory-Reader-GFR209 too, if there's not one already built into your computer. It tends to be much faster to transfer data off a memory card via a reader plugged into a USB port on your computer rather than hooking up a cable between your camera and computer mostly because the camera will want to transfer using some slow bit of unnecessary software vs the card reader presenting your photos in a folder that you just copy to your computer's hard drive. (Photos saved to your Lumix's internal memory have to be retrieved by plugging the camera into the computer and using Panasonic's software). *I've never had an SD card go bad though, not even my 32GB ones but but I prefer to err on the side of caution.

I just buy the ones at the counter at Microcenter and I buy them based on the optimal point on the price curve. Meaning that if the 8G is 1.7x the price of the 4G and the 16G is 2.2x the price of the 8G then I get the 8G. Unlike jamaro I have had them go bad but I am reasonably certain that almost always is a result of them getting bent/torqued. (I've grown to really be irked by the fact that most SD card holders on computers leave some of them protruding.) I don't think I've had one go bad since I started being more careful with that but maybe the cheapie Microcenter cards are a better quality than whatever I was buying before. At about $9 a card I really don't care if it craps out after a year. I've never had one die abruptly; they've always worked again after some TLC and reinsertion. After which I copy the stuff off and throw them straight into the garbage.

Doh, correct card reader http://www.amazon.com/exec/obidos/ASIN/B001AW8W7A/metafilter-20/ref=nosim/. I have http://www.amazon.com/exec/obidos/ASIN/B0028Y9BX8/metafilter-20/ref=nosim/ too, but because it's the size of a flash drive it is frequently temporarily lost.

Micro Center (by the Trader Joes in Cambridge, the one by the river) will have them for real cheap.