DC stick with 7018 rod is very rewarding once you get the hang of it, heck even 6011 on DC isn't bad, 6011 on AC is messy but definitely gets the job done!
If you just want to screw around and see if it's for you, get one of the 125A flux core welders from HFT, they go on sale for $100 or less all the time, they're tiny, handy and will let you see some things and make stuff. I've had the old 90A version (apparently the same thing, other than the lack of cooling fan and the gun is always live on the 90A) and I have built all sorts of things with it that are fairly sturdy. Only buy .035 wire for it if you do get one, you can't put it on high with .030... Many will complain that it isn't good and isn't DC like it should be and all sorts of things, which are all true but that doesn't change the fact that it gets the job done and $100 is more disposable than it used to be...
That said, definitely peruse the used market, if you can find an AC/DC Lincoln tombstone for $100-150 go that route! My favorite welder is an old Montgomery Wards AC/DC stick welder made by Century that I found at Goodwill for $20 with leads... but as said flux core is easier for smaller stuff and tacking things together but if you get 1/16" rods a stick welder will do anything a flux core welder will do but be more frustrating.