Yes you can have pethidine. Also gas and air. I had a wonderful homebirth with DS2 now 5 and am 26 wks pregnant with DC3.
I am planning another homebirth and have been lucky that(up to now!)I have had no probs with the pragnancy and had full backing from my midwives. We are only a 10 minute drive from our hospital.
Advice wise-
I have found the midwives very supportive of homebirth.
Visit your local pound store and buy a cheap tarp/waterproof sheet. Just roll it up and throw away after, saves loads of mess and worry!
My midwives only brought 1 cylinder of entonox and the assisting midwife had to dash back and get another, Make sure you request pethidine in your plan otherwise they don't bring it.
Have someone make up a clean fresh bed with clean nightwear/afterbirth clothing also, after giving birth, a shower and fresh clothes and bed are FAB so you and your newborn can have some well earned rest(looks better on photos too !
buy in some extra tea/coffee/biscuits for your guests, put it all out before hand with a sign saying 'help yourself'.
I agreed some hand signals with DH for when labour got too tough to string a sentence together, to indicate what I needed ie water, back rub, entonox, needing to push etc he could then relay all this info to the midwife.
Ask away if I can help anymore, As long as mum and baby are well and there are no complications that the midwives can't deal with I'd say go for it!!! Best of Luck
Frang x