The perspective & proportion thing can be scary to take on (it scares the muffins out of me *-*), but once you know the basic laws and rules you'll have it beat - you can be the best artist in the world but if you can't get to grips with 'the two P's' it'll hinder your ability to show the world how good you are . (... I mean, it's fine to have a wonky room if you're painting Alice in the 'shrink me/grow me' part of the story, but usually things aren't meant to look like that.... and having a body in the correct proportions will just make it look so much better! )
Below you will find links to deviant tutorials as well as a handful of other sites that may prove useful. The links cover learning how to get good angles, perspectives and proportions in architecture as well as the human (and animal) body - worth taking a look at even if it's just for brushing up on old skills.
Deviantart Perspective Tutorials
Deviantart Proportion Tutorials
Art Design Web: Aspects of Drawing - Perspective
Learn to draw human proportions
The Video Tutorial library of visual design guides
Comic Book Style Graphic Design | GoMediaZine
Fine Arts Video Tutorial Library | Sessions Online School of Fine Arts
The magic of painting
Drawing: Art Studio Chalkboard
I hope these are useful! ^-^
If you'd like to see the article about how to find good colour schemes and combinations follow this link - how to find complimentary colour sets
Also, as before, if you know of any good tutorials or sites to do with perspective and proportion please feel free to leave links to them below so others can find them!