Does anyone know of any place where I can get detailed descriptions and diagrams for the various throws and techniques such as Ikkyo, Nikyo, etc.
Sadly, though, detailed descriptions are pretty useless. You could try "Budo" , O Senseis training manual which used to be top secret. It's illustrated too.
If I'm looking for tips outside the dojo, I look for clips on the web. There's a couple here, a few more at the aikidofaq, some clips of O Sensei and Tohei Sensei around (I searched from http://www.google.com
, one site with pre ww2 clips) and a surprising abundance of clips made by the Yugoslavia Aikikai. Some are great. Some aren't.
Hope that's useful,