This really is something different - so different in fact, we've not grown them either (yet!).
We've located a small specialist grower in Holland who is developing ways to grow Avocadoes in Northern Europe. These fine trees are a great starting point.
They are of course tender, and thrive in humid conditions, so will need Winter protection - they can grow outside on patios fine though between late May and September. They will grow quite quickly at 50cm a year. They are already pruned, so this season will produce side branches.
It makes an attractive indoor plant anyway, forming a woody trunk with pleasant glossy leaves. They usually take 5-7 years to produce fruit on a mature tree, and have fruited in UK before - indoors and out. It's so new though, if we're honest we really don't know!! You will have great fun trying too, safe in the knowledge that virtually no-one else has ever grown one!
Very limited stocks.