kinda an oddly worded question as it doesn't really explain what you're asking...but anyway
since I assume you know that guitars require amps i'll spare you that...
PA- You can do this a few ways, one is to get a combo type PA that is a power amp and mixing controls in one box much like a guitar amp. Just remember you need a lot more watts then for guitar, at least that is what i've found. Try Soundtech, Yamaha, ect. The other way to go is a rack setup. In that case you need, minimum, a power amp and a mixing board. This is of course the nicer way to go as yes it will make recording easier later on. Add to that several mikes (shure SM58's are good all purpose) and you should be pretty well set. I wouldn't worry about enough to mike the whole band, as anywhere big enough for that should bloody well have their own PA system and 100w of tube amp goes a long fucking way....A LONG way. Oh and of course PA speakers, just stay away from the super cheap stuff. there are some decent packages on musiciansfriend and such that you could check out.
Recording- If you've got the mixing board this is easier since you can just mike everything and go at it if you want. Ideally, in this day and age, it is best to record onto a computer. Get a decent soundcard and recording program and go through the mixer to keep everything nice. You can also do a digital 8-track or better, and if you are really going cheap try tape....but it is a pain in the ass and sounds like crap in comparison. Our band went the computer way and it is really nice, just a smaller mixer will do fine and we can easily do things track by track...play back along with recording ect.
other stuff- For live always keep anything and everything you could possibly every maybe in any situation need for ANY of your equipment. Strings, tuners, screwdrivers, wire cutters, string winders, drum keys, extra cables, backup guitars (unless you are desperate always have more then one guitar), spare mikes, power cables, extension cords, batteries (for pedals), power supplies...whatever.
hope that helps. Bryant is right about the other part. You definitly cannot just let everyone do their own thing, and everyone needs to be honest and make it clear what their goals are, what they want to do, for anything to work. If everyone is just messing around, as fun as that may be, someone has to say "ok..time to work" or else nothing goes anywhere. Of course my band is the perfect example of all this and we have a lead guitar player that thinks he is kirk hammet and wants to kick ME out (rhythm guitar) because I won't let him take over. Actually we've been through quite a lot of lead players....