Hey man, few things:
1. You posted this in the main forum section. There is a sticky at the top of this that strictly states that this section is for
"Sneap Interviews
Sneap's own posts
Hell related stuff
Upcoming Sneap projects
etc
as well as moderator and admin posts (like this one for example)."
You probably see other threads not relating to this, however this rule was implemented a few years ago and people are bumping threads from before this rule being in place.
2. People generally frown upon people offering free work this loudly. While we all start somewhere, for some of us this is a full time gig and you'll generally get lots of flack.
3. Just a personal bit of advice from experience, it's generally best to not ask anyone to contact you with stuff for you to mix. These types of clients are generally not the types of bands you want to be mixing (usually not worth mixing, usually very poorly tracked/recorded stems etc.) and will most likely set you back more then move you forward. You don't have to abide by this, it's more of a suggestion
If you're looking for stuff to mix for practice, check out the practice room subforum, a lot of people post raw mixing tracks on there. If you're looking to develop a client base, I would suggest going to local shows (if there is a local scene) and talking to bands that you want to mix, not just bands looking for free work.
If you have any questions or anything, feel free to PM me and I can help you through some of this stuff. I'm actually posting some raw mixing stems this weekend for a video I'm finishing, so I can send you that way as well.
Cheers!