I caught your shoutbox stuff so let me just chime in. Or at least try and do something helpful.
Making a drawing come over as 3D is really a matter of shading and highlighting and adding the extra little details to your drawing such as folds in the clothing.
It's hard to explain, but when adding shading try to think of where the light source is and the areas where less light will be hitting the character as a result, such as the side of the nose, inside of an ear or anywhere like that. Take a look in a mirror and see for yourself. Or take a look at someone else's drawings and see how they've done it. Or both work just as well together.
The same idea can be applied to highlighting but instead you're adding light to the raised areas or those more exposed to the light source.
See what I mean? No? Yeah I figured I'd be bad at this. Not having any examples makes it hard. Mkay then, here's a
useful link that should hopefully provide you with some hints and tips, thouhg it probably doesn't quite cover everything.
I'd also recommend finding scans of the Phantasy Star Compendium. Seeing how you're drawing characters from PS II just now the compendium has plenty of pictures that make great references both for drawing characters and learning how it all goes together in terms of the highlights and shading. I'd say go buy some books but the lat time I bought some books to help out I was disappointed with the quantity of info on certain areas. >< But if you have the chance to take classes then do it. Odds are those will help more so.
And of course, practice, practice, practice! You are doing well Solar. This sort of thing just takes time and practice. The good thing is that it's all up to you whether you keep at it or not. Just remember, these
are people you are drawing here. Not exactly the easiest thing to draw now, manga or not. Don't push yourself too hard but always be willing to try and up your game a bit.
You will have your good days and bad ones too. I did today. I tried to create an original Amy piece only to get the anatomy on her legs screwed up. I'll need to try again later now. A couple of hours later and I started on a portrait of Flynn which went more smoothly.
oh and one more thing. I recently tried my hand at drawing the Data Memory girl. Though I intend to draw her again and get it right, the one you've got here turned out a LOT better than mine did. So there's a couple of points to you.