I have now 3 domains being backordered with godaddy and snapnames.

But Club Drop "don't see" any of these domains, one of this domain will delete tomorrow, the other two are in redemption period.

How does it work ?

Club Drop is kinda funny that way. You have to enter the name into the bidding que for the day that it is going to drop. It's a very specific system.

In fact, often if I try to do a search for a name that I KNOW is dropping that day, it won't show up in their search section, but I can put in a bid on it.

Hint... I have found that it is like eBay in that you should try to "snipe" your bid in on the name right before the cut-off time of 10:00am PST. Otherwise others will try to outbid you. At least this has worked for me.

there are other better offers for backordering

Which offers ?

pool.com namewinner.com

I'm already with those both two.

Namewinner is the one which twice in a row (the only two) has not send me any note about losing or wining a domain.
I find it exasperant.