4X4 problems

I need a little help, I have a 2000 Chevy Blazer (trail blazer option) that shouldnt matter. but anyway loud noise , sounds like a bad hub bearing comming from the front end. I dont know shit about the 4 wheel drive system, but i think its the transfer case in the front where the noise is comming from, anybody have a clue on how to replace these it looks pretty simple but i would appreciate any heads up if there are any little tricks or special things that need to be done
thanks

Transfer case is under your butt not up front, there is a front differential. Take it in for an alignment, if anything is broken they will inform you. They cant do the work(NTB or SEARS) so take it there.