As a side note, if you do get a bike on a shoestring budget get an older bike as those things were built to last; modern cheap bikes have gimmicky suspension setups (suspension is great but there are vast differences between cheap elastomers and a plush oil based setup) that don't help and add weight (and parts to go wrong) to the bike.
Also if you are finding it difficult to get into, try different styles of cycling. Fast road riding, cross country mountain biking, long distance cycle touring , downhill mountain biking and BMX riding are all vastly different experiences that use completely different skills and muscles.
On another note, if you get serious I do highly recommend so called "clipless" (a cleat in the shoe locks into the pedal) pedals for most styles of riding.
These things seem so scary and dangerous to start with, but I can virtually guarantee that once you are used to them you will not want to go back even for technical offroad riding. The extra efficiency and control you gain is astonishing, toe clips don't even come close. Of course make sure you practise on a grassy area first and get the feel for them and make sure you are confident with them before heading into traffic.
Falling off your bike when you stop for a red light is at best embarrassing and at worst really dangerous.
Also Sheldon Brown's page (RIP) on cycle maintenance though heavily outdated unless you have an older bike is probably one of my favorite parts of the "old internet".