You posted about improving your modeling skills, this might help.
1. Got to sites and clubs that are into modeling and hang out there.
The 3dartist's club has a speed modeling challenge, might want to check it out.
2. Get lots of tutorials on modeling and don't forget reference materials.
3. If you have drawing skills there is nothing like doing a bunch of thumbnail sketches of your next model. The reason is, when making something you have these vague ideas but when you do sketches you have chances to test variations in your model's design.
Instead of just going with what you think, you can make variations and go with the best idea.
I wish I had better basic drawing skills to take advantage of this.
4. Do not get frustrated, to be good is going to take time.
Take your time and learn.
5. To be good at modeling you need to make models, all the tutorials will not help if you do not do any modeling.
Do not worry if its crappy, if you keep working at it, improvement is guaranteed.
6. Keep your old stuff.
I have talked with people who have dumped their old stuff because its not their latest and greatest. They almost feel shamed to show their old work.
When you feel like you are not progressing, taking a look back at your old stuff will show how far you have gone.
Nothing like having a history, might give clues on your future.
You don't have to keep the old stuff in your portfolio but keep it somewhere so you can look at it.
I have kept all of my old 3d stuff even when I did nothing but landscapes.