Hi
As MckenZiecz was saying saying mig welding is the most easiest and cost affective. As Being a welder (apprentice) tig welding does take a lot of practise.
But when it comes to owning one were talking a lot of money. It's a couple hundred for a cheapish machine, about £50 for good helmet, thick wealding gloves a leather apron or jacket. All in all that's about several hundred there it would proberly be cheaper to go to a decent garage and get them to do it for you.
But if you want to learn to weld go for it. It is a good skill to have And mig is the best one to start of to learn
Key
Tig - tungsten inert gas
Mig - metal inert gas