How in the heck can I watch Oakland A's games live?

Got any friends who have cable TV and an extra set-top box that they don't use much? Buy a Slingbox, give it to them, and have them install it on their spare/underutilized box, then connect to it to watch games. If necessary, you can offer to pay whatever it costs for them to add another set-top box to their existing installation, which is usually pretty cheap. I did some Slingbox trading back in the day when I wanted to watch Philly-area channels from here in Pittsburgh. I didn't do it for baseball because the MLB.tv streaming package is fantastic, lets me download the videos and skip through them instantaneously, etc. But I would be screwed by the same blackout rules if I still lived in Philly.

CSN-CA (CSN California) is one of the local Comcast sports channels. The other is CSN-BA (CSN Bay Area) which broadcasts the Giants game. I was under the impression these are both channels available on the lower tier Comcast packages. I'm wondering if the sales rep you talked to wasn't trying to upsell you? Maybe try calling back again? I have no personal experience with this but a friend of mine recently used https://www.hidemyass.com/ VPN service to watch Netflix in France and was happy with it. I'm not sure if this falls within your definition of legal but really, mlb.tv with a VPN service is most likely the cheapest route. I totally sympathize - I hate blackout restrictions and hate cable companies even more.

I have this exact same issue. (Let's go Oakland!) I've looked into the MLB.tv/proxy concept a little bit myself, but one potential problem I've heard of is that MLB.tv blacks you out based not just on the location of your IP but also the billing address for your credit card. I don't know if this is true or not but it's one of the factors that has stopped me from trying it out. The lengths that MLB goes through to prevent me giving them money are ridiculous. Guess what? I'm not going to pay for cable so you're getting NOTHING until you allow streaming of local games. Well done!

So, I called Comcast, and the cheapest package I can get from them that includes that package is 84.99 a month. We currently pay 39.99 for our internet, so more than doubling our cable bill just to get the one channel I want to watch baseball games seems ridiculous. Well, the cheapest package that Comcast has at all is $29.99 ("for the first 12 months"). I couldn't get their website to tell me straight whether this includes the CSNx channels or not, but assume it does. You would still be paying 30 + 40 = $70 for internet plus minimal cable, so realistically you are only looking at an extra $15/mo to guarantee access to the specific thing you want. Maybe call back and specifically ask about the entire channel lineup for the "Digital TV Starter" package, which is the cheap one? That's probably your best bet if you really want to keep your current internet and save $15/mo.

As a possible compromise solution, the radio feed package from MLB.com is only $20 for the entire season, and not blacked out anywhere. Also, MLB.tv offers up one free game a day, so keep an eye on the schedule and you'll at least get the occasional game that way.

one potential problem I've heard of is that MLB.tv blacks you out based not just on the location of your IP but also the billing address for your credit card Not so. Otherwise nobody in Canada could hide their IP address and watch Blue Jays games, and I assure you that they do.

I pay $3.99 a month for a proxy and haven't had any issues watching Giants and A's games. I use bestproxyandvpn.com. It feels a little spammy, but it seems to work fine.

Any idea if I can use these proxy's on an ipad?

I haven't gotten the HMA app working right yet on the ipad, but I did go the MLBTV subscription route and can at least watch games on my laptop / projector setup. HMA is working for watching games live, at least for now.