We attended a sossidge-making party recently. We used proper sheep-gut casings which I think our host had bought online - I'm seeing her this evening so I'll ask for the URL.
For tips - get a proper sausage making machine. Our host's was a fairly cheap and simple one that doubled as a mincer, and you simply removed the blade and attached a nozzle so stuff the casings.
Get lots of casings, and don't be afraid to sacrifice a few as you learn how to stuff them. It can take a while to get the knack.
Don't stick your finger in the mincer. It hurts.
Fry up a little of the meat mix you're going to stuff the sausages with before stuffing and taste it. This allows you to adjust the flavour balance before committing yourself.
Look online for techniques concerning the blend of fatty meat versus lean. Our host had done her homework and was guiding us, but I can't remember exactly the recommendations.
As for recipes: beef, chocolate and chilli work well, but can be a bit dry if you're not careful. Otherwise, we had a curry-themed barbecue later that month (all kebabs had a curry marinade, the potato and rice salads were all to indian recipes, etc) and my friend made some nice lamb-lentil curry sausages.
