Not a bad time of year to be sowing a few things.
In October I plant a few Japanese onions, its late so get them as sets (little baby onions). They're not the
most useful crop, in that onions are dirt cheap. But they're quite fun and they'll give you a crop of onions a month or so before the main crop onions are ready.
I also sow a few peas at this time of year, at the end of the month. Go for a variety that is really hardy, like 'douce provence' or 'feltham first'. If you can cover them with some fleecy stuff when the weather turns really parky that'll help, but they should over-winter with minimal losses. A good idea is to soak them overnight in water, then for an hour (no longer) in paraffin, you get better germination that way and less risk of mice eating them.
Broad beans... Yep, but down in the South here I hold off till November. 'Aquadulce Claudia' is the best bet. Not the easiest of crops, there are some tricks to getting a good yield; dig some muck or compost in before sowing, ask again in Spring when they're in flower.
Garlic goes in during November too. Go for a soft neck variety for storage. You can also get autumn planted shallots.
Is the site sheltered or can you construct a simple cold frame? If you can, I'd also sow some winter lettuce ('arctic king' is good), rocket, mizuna, mibuna, etc. Basically, lots of salad leaves that'll survive cool weather.
Now is also a great time to plan out where any fruit plants will go. You're best planting those from late autumn onwards, so if you'll be wanting currants, raspberries, loganberries, boysenberries, tayberries, apples, pears, or anything else really, its almost the time to look through catalogues, get to the shops, and pick things out.
Now be careful... Right now you're looking at a nice, clear 10' by 15' and thinking that its a lot of space, but it isn't. Don't fill it up with a couple of crops that you can easily buy; its questionable whether growing onions is worth it, and it probably isn't even worth it for garlic. In that kind of space concentrate on what you really like, and what is really expensive or impossible to buy. Do you really like green salads, do you want the kind of expensive looking stuff you get in bags in supermarkets but with flavour that you can't buy? Concentrate on those. Carrots your thing, do you want root veg of a quality that can't be bought? Grow carrot varieties like 'sugarsnax', 'purple dragon' and 'red samurai', and other roots like salsify, scorzonera, celeriac and kohl rabi (all quite delicious). Like potatoes? Good for you, but if you're going to grow them stay away from the main crops and concentrate on earlies, get those lovely new potatoes and continue buying the main crop ones at the greengrocers, don't devote your time and precious space to it. Herbs give you best bang for buck (highest value and most flavour per unit space), runner and french beans are exquisite fresh, sweetcorn straight off the plant is amazing, beetroot is so sweet when fresh you won't believe it, once you've had your own mange tout and peas you'll never buy any again...
Go browsing the seed company sites now for what you want for next year; I reccomend nickys nursery, real seed company, seeds of italy, as well as the bigger companies like kings, thompson and morgan, etc. Some good bargains to be had from seeds by size, if you can work out how his web site works
Segregate your sections off for a simple rotation; you'll never stick to a strict crop rotation, but don't grow the same crop on the same place within a couple of years. You'll save yourself a lot of trouble if you stick to that advice!
And, last bit of advice is don't worry. Really. You'll see weeds, carrots struggling to grow, cabbages being eaten away by pests you can't see, parsnip seedlings disappearing in the wilderness (although theres a trick to parsnips...), fennel running to seed, onions rotting... Don't worry about it. Some you win (most, in fact), some you lose. Thats just how it is. You'll be amazed by how many you do win; I guarantee you'll be worried about whether things are growing or not or whether you're going to get any crops at all, thats normal