Employment Agencies in the UK

Well I just came to the UK and I started looking for a part-time job to earn some money for my living before I start University. I have been looking for information online on recruitment agencies and how they work in the UK and most importantly whether they are reliable. I have read this article http://www.iamintheuk.com/565/employment-agencies/ and now I am totally confused on whether I should bother with agencies or should I start looking on gumtree and so on. Btw, do agencies help you with visa requirements (this is not for me since I already have visa)?

Heya - I would imagine different agencies provide different services. I once applied through a few of them for various jobs in the UK and found that the actual companies you'd be applying to, they would usually arrange the visas but not the recruiter / placement agency themselves.

I think you should look everywhere. Use the recruitment agency but also put yourself out there on gumtree and stuff too. Can't hurt, right? Could expose you to more options and opportunities.