Hey there cedricpokerheaven,
I only play at 888 & Stars so they are the only rooms I can advise on.
You can buy into all of the Micro Limits at 888 with 20BB's NL2/NL6/NL10
Once you move up the the "Low" Limits, you have to buyin with around 35BB's
It may also be helpfull if you post which limits you play so users will be able to qiuckly checks their rooms for you too