we still haven't tried meat, but DS is only 6mos, and the baby food book i'm working from is anti-meat, so i'm not sure when to introduce them. i'm very pro-meat, so i will be looking for another source that deals with that.
citrus should not be introduced until 1yo, or later if your baby has other allergies. citrus is very allergenic, not to mention the acid can burn their bums, as PP noted. being allergic to citrus myself from a very young age, that is definitely one that we will avoid for a long while yet. as far as where i read it, my baby food book, Super Baby Foods, and also my baby book, Your Baby's First Year: Week by Week.