Vegatable growing Month-by-Month by John Harrison is invaluable, as it does exactly what it says on the tin! It's available fairly cheaply from Amazon, or if your budget's REALLY tight, check out your library. Agree with what other posters have said, re Wilkinsons and Aldi for seeds, but not just for seeds. Don't know if your aldi will have any left, they were doing fruit trees for 3.99 last week, this week they've raised bed kits, 3/4 tier PVC greenhouses, flowers in pots, etc etc. Poundstretcher is good for gardening equipment too, I got a massive packet of fleece (for warming the ground prior to planting, and protecting tender perennial flowers) last year for about a fiver. Don't bother with cloches, cut the top off a pop or squash bottle and use that instead.
If space is limited and you want to grow things in hanging baskets, try the easy-fill ones available on t'internet. They're a lot easier than the traditional type baskets, can be re-used year after year, you don't damage any of the plants you're planting as the whole rootball goes through the planting gap. Sites like ideal world will have videos on how to use them (but don't buy from there as the postage is astronomical). I won't use anything but the easy-fill baskets now, no, I'm not on commission for them, but I was a novice a couple of years ago, and the range of stuff on offer is bewildering.
One top tip I've learned is to keep a garden diary, so record what type of seeds you've sown, dates of any late frosts, how well seeds germinated, how well they grew (and whereabouts you grew them), and most importantly, how well they cropped.
Grow stuff that's expensive to buy in the supermarket, runner beans are very expensive to buy, but half a dozen plants will be more than enough to supply a family of 4 with some left over to freeze.
Like you, I'm on a very tight budget, so I do things like save yoghurt pots to use as plant pots, make my own compost (but very much a beginner on that, other folks can advise and are brilliant on here). There's no such thing as a stupid question to a gardener (other than would you like a cup of Tea?), folks on here are lovely and have given me no end of brilliant advice.