We have a special forum on this board for BOMs:
http://www.quiltingboard.com/sitemap/f-9.html
I would check there first. There are several in play with lots of discussion.
Also, do a google search for them Blocks of the Month. Usually (but not always), a BOM will start in January, however, some sites will leave the info for previous months' blocks until the quilt is complete, so you have a chance to catch up. Some take the older blocks down.
Finally, check with your LQS. Many shops will run one or more BOMs with monthly meetings etc. Some sell BOM kits and some just sell the pattern. Also inquire about other monthly clubs like "Buck a Block".