The investment in running shoes is well worth it, if you plan on doing lots of running. Heck the price difference is worth it in the savings from extra pain killers alone. Or in one visit to the doctor.
Back when I was in HS I ran a 5:20 mile, but nowdays my knees arent up to the challenge. Instead I ride my bike to get excersize. I usually ride on the weekends anywhere from 6 to 14 miles in one ride (half of it being up hill).
Steve, running is great for you. I peaked out in high school when i ran the chicago marathon.
first advice. white tidies. you will never father children if you try to run in boxers/just the shorts. I never figured out how guys could do this on our team. Perhaps they were masochists, or maybe they were flat cchested women pretending to be men.
second, get yourself some shoes. i know you aren't sure how long this is going to last, but trust me. your joints with thank you. I bet ten bucks anapalooza is having joint issues from running in the wrong kinds of shoes. you don't have to go nuts and buy some $150 shoes, but go to a running shoe store and ask them what kind of training shoes they have for around 60. from what you've said about you size (150-160 iirc?) and general athelitic-iness you should be fine with that. I get the feeling anaka is bigger from all the lifting so he might want to invest in something with more cushioning.
third, don't do speed work outs every day. mix it up. you'll have more fun on your runs if you go different places. the best places to get a nice runners high are surrounded by trees. the extra oxygen makes the run easier and the little buzz you get lets you run longer than you could before. at least twice a week switch to long slow jogs for longer distances (6-8) miles, later 8-10, don't do more than 15 unless you're marathon training. don't kill yourself, you can get great results from surprisingly little work, and if you run in parks/forest preserves you could meet some hotties.
if you want to get your times down, find a track or a nice flat place with something you can use for judgingdistance and when to start and stop. Do the math to figure out how fast you want to run a longer distance and break it up. say you want your three mile time under 18 minutes (decent for starting race time). that's 6 per mile. 3 per half, 90 seconds for a 400. so run several 400s at under 90 seconds with equal rest. you'll eventually teach your muscles to want to run those speeds. I used this method to bring my times down from ~18 min to just under 16 minutes for a three mile race. I never broke 15:30. that's really hard for us white guys.
If you'd rather just get in shape, do more of the longer slower runs and stop somewhere in the middle to stretch, take a short break and maybe do some crunches or isometric pushups. Also, don't forget to always walk the first 50 or so feet and walk the last 100 or so feet to warm up cool down. if you just bust out there, you may pull something.
I like to plan it so I end up some place with drinking fountains, that way I don't have to carry anything. The really soft kind of grass is also a bonus.