One thing I'd like to add to this list is this:

Don't assume that more expensive is better! Many hobby shops and specialty tool companies online will capitalize on this. You'd be surprised where you might find a tool you need to get a job done and just how cheap they can be. For example, hobby stores will sell you a package of sanding sticks (basically just popsicle sticks that had sandpaper glued on them) for a small fortune ($10 for a bag of 5). But if you look in the cosmetics department of any store, you'll find the exact same things for polishing nails for $1.00 for a bag of 50. I know I have made alot of my own tools using the wire from Wire Coat Hangers. If you take a piece of wire and hammer the end flat you can use a dremal to shape that piece into whatever tool you want. I made a scribe tool for etching panel lines like that. Same thing goes for air brushes. I have a $40 airbrush set with a cheap compressor that I got from Testor's a long time ago that still works. I can produce the same effects with it that a $300 air brush and compressor can. But I feel comfortable with it. I know how it works... and that's the key. Don't spend tons of money on something that you will only use once. You really can't justify a purchase of a $700 table saw to cut one piece of a model you are currently working on when you can produce the same effect with a $5.00 miter saw and a little patience. Think outside the box. Think about a problem you're dealing with before you actually do it. I call it "Zen Modeling"... Think about how you're going to handle the problem and how many different ways you can tackle it to find a solution. Experiment with different methods in similar situations until you feel confident enough to commit it to the model you're working on. FOR SALE signs are a great source for practice styrene sheets. You can cut them up and glue them together to create practice parts for painting. Those clear plastic bubbles that just about everything is packaged in these days make great scale windows. I don't know how many times I've burnt the plastic/paper off those twist ties that my ex-wife would collect from bread bags only to use the thin wire for a detail here or there. It's amazing to think that 90% of the things you use for building you can find around the house and you already have it. I know I've discovered that if I mix a little Future/Klear/Pledge Floor Wax with the a drop of ink from those printer ink refill kits I can produce the perfect window tinting or fiber optic coloring! I learned that by experimenting. Enjoy it... you'll find you'll be looking at that kitchen utensil in the housewares isle of the supermarket a little differently! :)