INDSKYS brings up a lot of good points. I used a $40 harbor freight gun to paint my 72 (body and hood blackout). For Painting my lower mach 1 stripes (6 or so months after painting the car) I bought a Devilbiss Finishline III HVLP Gun. I have only used it once now and it is amazing.
With the cheapo HF gun there was a couple runs and tons of orange peel when the gun is adjusted as best as I could get it. It was very hard to clean up and tended to drip a lot (even with every joint having teflon tape on it).
The Finishline 3 (FL3)gun is just amazing. I put it all together, ran some solvent (thinner) through it a couple times along with adjusting the regulator at the gun, inserted the EZ liner (a must have, it makes for very easy cleanup), put some paint in and adjusted the air/paint mixture and fan control for about 2 minutes. After all that I started spraying, and man the results were amazing.
The gun was very well balanced when full of paint, the paint laid down perfectly (very smooth and no orange peel at all). After painting I spent about 3-5 minutes total cleaning the gun back up.
The FL3 is not the most expensive gun out there, but it was a night and day difference over the cheapo or semi-decent guns. I bought mine from Len Stuart at the autobody store (
www.autobodystore.com) for a great price and fast shipping. Spend a day or two and read through the message board on that site. If this is your first time painting invest in the Paintucation tapes (i have the entire set and they are immensly useful). Stuart also has a video tape but I havne't personally seen it to comment accurately abot it, but from his knowledge and experiance in painting and autobody I bet it's also first rate.
Here's some points to remeber/consider
1) spend the lil extra for a good or great quality paint and not knockoff cheapo brands. If you don't you'll probably regret it in a year or two when you have to repaint again.
2)take your time and prep the car very well, don't skimp on things. Paint and bodywork takes a lot of time and patience along with a lil bit of learned skill. Don't be afraid to make mistakes, but do take the time to learn, ask questions, and fix it before continuing on to actually painting the car.
3) You will have to create a clean paint booth. Whether it's a custom 2x4 frame with plastic sheeting and fans or cleaning out your garage it's important to have a clean work area. This is so dust and other contaminants (bird poop) doesn't get in your paint as it is sprayed or as it dries along with protectin other htings from overspray and health hazards. I helped mike out on here paint his 65 in his open driveway, but he can attest I wasn't happy about this.
I painted my 72 on a concrete slab surrounded by dirt and under a 12'x 20' enclosure that the sell at costco ($169). I did have a couple dirt specks in the paint even though i was anal about wetting down the slab and yard very well along with being analy retentive about cleaniness of the car and my clothes. Those came out with a little color sanding and buffing though. They can't be sanded out everytime (i.e. if it's stuck between the base and clear coats) so be very careful.
4) what system are you looking at (i.e. base/clear coat or single stage urethane). SSU is very hazardous due to isocyanides in the hardener and should be used with a fresh air system or approved respirator. Some clear coats are this way also. In some cities they will not allow you to paint a car with paint that has isocynides in it (or if you do you'llbe fined heavily). So check with your city/county. Along with buying a good quality gun, buy the best respirator you can buy that matches your intended use.
I have tons more tips just not the time to type them up (as i'm sure INDSKY's does)