you can join in any time. at the top of the "Main" section (in the blue) you'll find the BOM rules and list of links to the blocks we've posted so far. We are using a different system now, but the list is still good. If you want a turn picking the block, send a PM to Boo and she'll add your name.
You don't have to be on the list to make the blocks.
You don't have to make any of the blocks you don't want to make.
You don't have to send the finished blocks to anyone.
You don't have to post pictures, but we sure hope you will.
The only rule is HAVE FUN!!!
:P