Kevin
I've always mixed my chemicals (for over 30yrs...).

- The difference between devs is not so big as it may seem. The Film Developing Cookbook will lead you in the right direction.
- It's more important to use a dev until one is fairly familiar with it before trying a new one.
- For papers it's the same - there are basically warm tone and cold tone ones, from there on dillution will cover about all your needs.

In the WEB, take a look at:

http://www.darkroompro.com/frames/index.html
http://www.jackspcs.com/index.htm
http://www.pofig.net/photodb/mainMenu.do

Re ascorbate devs, Patrick Gainer (he posts on APUG from time to time) has done a nice job.

Here's the start page for his devs:

http://unblinkingeye.com/Articles/VitC/vitc.html

HTH

Jorge O