I just started using a new site etc. for mailings. It's worked out great and I thought I'd share.

You can create an account with the United States Postal Service (usps.com) You then have the ability to create mailings, postcards, etc. All you do is download your document and list of names and addresses. They then print and mail your documents. The postage prices are discounted with a small amount charged for printing. (it is still usually less expensive than paying the full postage price) If you have non-exempt status with the post office, postage prices are even less than the discounted prices!

We've been using it for our fundraisers. Ex: For our bingos, we log names and addresses from the ticket stubs into an Excel spreadsheet and send postcards to announce the next bingo or event. It's worked out really well at getting the word out.