Another Egan book well worth reading is Schild's Ladder, which reminds me a lot of Diaspora and was recently reissued in the US:

http://www.amazon.com/Schilds-Ladder-Novel-Greg-Egan/dp/1597...

If you don't mind highly technical hard SF, Schild's Ladder is also very good. It's not explicitly spelled out in the text, but it serves as a good pseudo-sequel to Diaspora.

Egan's publisher recently ran off a new printing of many books in his back catalog that were hard to find in the US.

http://www.amazon.com/Schilds-Ladder-Novel-Greg-Egan/dp/1597...