If your only after one item & the shop near you has it I'd just go there for sake of ease.
As for me getting in to it, I did kick-boxing for a fair few years as a young'un. Long story short a friends Dad worked with a guy from Holland who had kick boxed for most his life, not in any serious sort of competitive way but more a self-defence/fitness thing. But they have inter-clubs & whatnot & apparently he did better than most. When he arrived in Aus he set some stuff up in his backyard, mini-ring, couple of heavy bags, floor to ceiling, speed ball etc. Myself & my mate were over there one day & just mucking around & he offered to train us, in an informal way, & it just went from there. He ended up with about 8 to 10 guys & that was about it. As we got older the training got a sh*te load harder but it was fun. My young'un is the one who does the MMA stuff now though. He started doing Kyokushin when he was about 5, moved on to a more MMA styled school & has just been told he can start training in a Gracie BJJ adult class. That has him excited, though at 12 I'm a bit worried.
As for starting out I think it's worth it. I wouldn't even entertain competition as a thought just yet though. The fitness, self-defence & social side alone make it worthwhile BUT be sure & do your homework on the instructors. With the sudden influx of interest in UFC over the last few years it seems any & everybody is an "MMA" instructor now. But if you get some idiot who learnt his trade off the internet trying to teach groups of people how to do crowd favourites like RNCs or Kimuras (or my fave the D'arce choke :lol

you will very easily & quickly get hurt. Hell even a simple move like a key lock can go arse up if your not careful. But I would say try it for say 6 months if you have the drive atm, keeping in mind no matter how fit you are grappling uses every muscle from your neck to your toes so you will hurt like nothing else for a while... Lmao.