I'm yet to find a simple, comprehensive, reliable guide to supplements for vegetarians and vegans. So instead of spending more time on Google I figured I'd just ask you all what you do.
I'm lactovegetarian ("veggie-no-eggs"). I take creatine and beta-alanine supplements. With the usual caveats (anecdata, placebo effects) I noticed a huge difference in the gym after I started taking creatine supplements. I think it's likely I should be taking some other stuff (B12? Iron?) and plausible that the beta-alanine isn't that useful.
There's some other interesting Forum content in the "Dietary Change" topic. This guide looks useful but is 474 pages long (!). I've found Elizabeth's posts on Examine.com's vitamin reviews and testing vegan nutrient levels somewhat useful (but wish there was way more of this kind of research!).
VeganHealth.org at least looks useful and reliable to me, but I don't know how good their evidence reviews actually are.
What supplements do you take? And what resources have you found helpful?