buy a cookbook and experiment. but knowing myself, i'll just fall back into old ways when i'm lazy - this means a lot of rice, a lot of toast and peanut butter.
Chicken and Rice will suffice.
For good cheap recipes, try the netmums website. I know it's supposed to be for mums, but they have good, cheap, easy recipes. I just compiled a nice list of recipes off there. It also gives tips on how to save money shopping for food too. Best website i've found, as it doesn't have all the fancy food that other recipe website have.
Salad fajitas = yum yum yum
I lived off curry and rice. Also had the odd takeaway and ready meal.