It al depends on what sort of welding you want to do, i have just come back from work where i had a go at alloy tig and tbh i found it pretty easy and got the hang of it after 2 days of twating on. If its on cars i'd just buy a few sheets of mild steel and a little mig welder and just tway on for a few days. Its not difficult it's just practice and knowing what works ie what speed power etc.