Hi There
There is a really good overview of all UK passive investment options on monevator.com it is UK based and I found it really useful when setting up my investment plan. They have a whole section on passive investing, and a summary of the cheapest UK funds for each asset class, including vanguard and competitors. It's really worth a look.
If you haven't already read it, I found Tim Hale's book 'smarter investing' really useful to. It'd UK focused and give a nice introduction to the whole passive investment approach and how it implement it in the UK. It can be a bit heavy in places, but if you are going to invest it's good to have an understanding of what't involved.
I buy vanguard funds every month through an online broker called Alliance Trust. It costs UKP 1.5 per trade, and is the cheapest way to access vanguard funds, although I think the ETFs are available through other brokers. You could start with the Vanguard All World ETF and team it up with their Global Bond Fund. If this is confusing just have a read around on monevator to clarify things.
Finally, if you really want some help, I talked to a firm based in the UK called Rutherford Wilkinson, in the end they couldn't work with me as I am currently based abroad at the moment, but they were very helpful all the same. They only follow a passive investment approach and are not stupidly expensive as far as advisers go.
I only started all this investment business last year, but did quite a lot of reading around the subject from a UK perspective so feel free to ask any questions, and I might be able to save you some time! Really though, the monevator site is a better source of information than I am!
Good Luck!