That old 4wd sounds good to work on for this type of learning (On modern cars it's just way too hard to come close to matching the paint finish and quality - best left for the experts)
On the old one if the 4wd has metal panels like a normal car (not aluminium like some English makes they require special primer), remember to covert any rust - never let rust form #1 mistake for first timers who do body bog work let the metal rust - uses zinc primmer if you can't get it all done in one go.
Prepping here is a good link, plus there are lots of great books if you look on amazon - American hobbyists have written lots of great literature.
http://www.autobody101.com/forums/vi...hp?f=5&t=16694
Paint for the novice Acrylic with thinners, 2 packs types that professional's use will harden in the gun if you take too long - but do give a gloss finish off the gun.
The standard Acrylic mixed with thinners is easiest to work with an on an older car can be polished to a very expectable shine by using say 3M colour sanding paper (very fine with soapy water) followed buy a cutting compound, then a polish - usually with a high speed buff.
My best gun is an old CIG bottom fed suction (my fancy low pressure gravity fed ones do not hold a candle to my old CIG unit) so yes it's a bit hit a miss to find a spray gun that works great for you and price is some time not the only guide. Tip sizes etc. play a big roll and long with pressure drop and the hose to the gun ..... always invest in a good condensate / regulator - can't afford to have water getting though while your spraying.
All it takes is money, good paint products - avoid those dirt cheap auto paint stores (you get what you pay for), heaps of patience and experimentation and when polishing not to burn though the edges corners.
Have fun.