I need help. I have a very snappy three year old westie. Tonight, hes just bitten the decorators finger. Hes been friendly all week and now just turned when he was moving him off his cloth. Im now at my wits end. I dont know what else to do. He hasnt been neutered yet but a vet I spoke to a while ago said this would not improve his behaviour, any suggestions.

Your first step should be to ask your vet to do a thourough examination (including blood tests) for any medical problem which may be causing this behaviour.  If this comes clear (and even if it doesn't, as some conditions need vet treatment as well as approaching from a behavioural side) you should ask your vet to refer you to a recognised behaviourist (preferably a member of the UKRCB or the APBC).  It would be very unwise of me to advise over the internet (and unwise of you to take any advice from anyone on the 'net) as agression can be triggered by so many different things, it would need an experienced eye to observe the dog 'in action' so to speak.