Where can I find programmers with experience in automating data collection from various formats (emails, PDF or Excel attachments) or directly from a list of public websites that have authorized me to collect data?

It  like what you want to do can be done in R.  Consider posting here: http://www.r-users.com/

There isn't any expert who can be affirmed the best for data collection. If you are looking for a long term and well experienced data collection proficient go for someone with a certification relevant to that web research industry or data collection function. If web data collection has been done through in-house team, it will result in increased operational costs and time consumption. Outsourcing always proves to be a graceful solution for your data collection (i.e. emails, pdf, excel attachments, etc.) needs which will benefit you more than just money.http://www.habiledata.com/data-collection.php?utm_source=referrer&utm_medium=quora&utm_campaign=quora-cpis the largest data collection agency all over the world. Regardless of your data collection needs, we are ready to complete your project with hundreds of professionally trained web research experts with all the technological tools. Skilled data collection experts can turn any deadline into reality.We take your search for relevant information very seriously and apply the most modern approaches to the research and acquisition of relevant information. Sometimes we use the latest software that will make it easy for you to analyze and interpret the information we obtain for you.

If you can get the information in the formats you listed (emails or attachments), you can parse out the data to Excel, Google Sheets, or wherever else you want to send it with https://mailparser.io?utm_source=quoraJust forward the data to an account you set up with them and tell the software how to parse it into the format you want. Then you don’t have to pay a developer to do it, and you get the results in minutes.But if you want to find a programmer, then http://www.upwork.com is great. The new oDesk.