there's a lot out there. i'd suggest starting with musictheory.net. there's a lot of material there that can be useful if you put in the time. learn and practice scales, learn 'the box' (google it), and you'll be ripping it up in no time.
stay away from open strings when you can. not that you can't ever use them, but learning to play up the neck will teach you a lot more than playing songs that are half on open strings.
it'll come with time. took me a while too. eventually, you can do some simple strengthening excercises like pushing down against the edge of your desk with your first and third finger (in a nice rounded position, no straight fingers), then flopping. nothing too strenuous - don't give yourself carpal tunnel - but just a light push. round your fingers so your palms are parallel with the desk. promotes good hand position. you can do it with both hands, too, since it'll help strengthen your right hand and increase endurance (probably my biggest issue generally). another good one is to tap the first two or three fingers of your right hand in order (not at the same time) against your desk lightly at a decent speed (about four taps a second...time it with the clock in the room). really lightly, don't attract attention. see how long you can keep it up before your arm starts on fire =) another endurance thing. eventually you can increase the pressure and do it against your leg or something. the trick is to NOT do it faster and faster, but to stick with that time limit. it'll prevent you from speeding up when you play.