Growing hops is really a fun thing, but can take up a lot of time particularly at hop harvesting time when you have to dry the hops, although you can brew using green hops. You also have to store the hops and that may require investment in vac packing or similar. However I store my hops in poly bags in my beer fridge, because otherwise they would take up too much space in the freezer since they are leaf not pellets (obviously)
Anyway long thread on hop growing here
Hop plants/rhizomes - growing report
There are others so use the forum search engine.
In short you buy a certified rhizome (rootstock) and plant it in the dormant season as others have said. It must be one that carries female not male flowers. Growing from seed is not advised. First shoots should appear in March/April time dependant upon where you are in the UK
There are mainly two sorts of hops, regular hops that can ultimately grow to 7/8 metres, and a small group of dwarf hops including Prima Donna (or First Gold) which grow to about 3 metres. In both cases you select about three strong shoots and then allow them to grow up strong cord or over something since they are strong climbers . You can grow them in large pots but in the ground is better. I have 2 Prima Donna in large pots.
A rhizome will take 3 years to come to full capacity. In the first year don't expect much
And when you have harvested the hop cones (flowers) at just the right time, in August/September time in a window of about one week, you will then have to thoroughly dry them for storage (unless you use some to make a green hop beer)
To buy try these people, there are others I'm sure
Essentially Hops
Finally you have no real knowledge of what the %AA is from your crop, other than by rough comparison with commercial varieties, so they are only ideally used as flavour or aroma hops. That said I guessed my%AA and appear to have got it about right so use them as abittering hop in the single hop beer I do with them.