Finding an allotment
If you like the idea of having an allotment get in touch with your local council. They will be able to send you a list of various allotment sites near to you.
While it is obviously sensible to have one as near as possible to your home it's worth looking at others as they can vary in terms of amenities and ease of access.
The council will be able to give you a map or a list telling you which plots are available but before you put your name down for a plot it's worth doing some homework before committing to a year's tenancy.
Visit the allotment on a weekend when allotment holders are likely to be there. Most will be more than willing in giving you a bit of background about the allotments and the plot you have your eye on, particularly if it's overgrown and blowing weed seeds in their direction.
Struggling to find an allotment? Read Terry Walton's guide to getting an allotment.
Questions you should be asking
Ask about the history of the plot. Who owned it before? What type of vegetables did they grow successfully? Did they add much by way of manure or compost? Did they grow organically?
Ask about the soil in general. Does it dry out or get waterlogged easily?
Find out about the amenities. Is there easy access to water? Is there space to park a car? Some allotments have restrictions on structures, so are you allowed to build a shed or greenhouse?
Find out about the allotment association. There might be an allotment association that sells seed, compost and pots at a discount. They may even rent out light machinery.
Find out how secure the site is. Security might also be a concern so ask about vandalism and pilfering.
Don't be shy! Allotment holders are generally very welcoming folk.
Related: how to grow fruit and vegetables.
Weeds to watch out for
Examine the weeds on the plot. Convolvulus, couch grass, horsetail and ground elder will means lots of digging to eradicate it.
Don't necessarily be put off by a bramble infested plot as they often block out light from other pernicious weeds and can make life much easier after the initial clearance and grubbing out of roots. If you're faced with a thicket of Japanese Knotweed however…walk away quickly.
Once you've made your choice plan to start work on it in the autumn or winter. This will give you plenty of time to work at a steady pace to clear it.
Don't think you have to clear it all in one season either. It can be done in stages and will be less overwhelming.
Related: how ground cover and control weeds.