cndij, if you are a member (even if you haven't gotten surveys recently), you can go to www.erewards.com to check your account. If you use the computer you usually use, they'll probably remember your name, but even if not, click "Log in" or click on "My Account" and you should get a log-in screen.

If you remember the e-mail address you use with the account, and your password, you can log in. Even if you can't remember your password, so long as you remember which e-mail account you used, you can enter that and click on the "forgot my password" (or something like that) link and they'll send you your password. Your account should still be there unless you've cancelled it.

As to invitations, I haven't received any recently, but am told that Delta Skymiles is sending out invites if you ask them. Don't know if that's true or not. I also seem to recall that if you go to the e-rewards home page there's a place you can request an invitation. Don't know if it comes when you request it, though.