[quote:c7e26d7245="oli"]It doesnt really affect the way I speak as such - more what I say. I come out realise loads of things I missed out telling them and I could have put things in a different way etc. If I was more relaxed then these things would just come easy - I had an interview a couple of months back for my current job - it was more just a chat - we sat down and just had a laugh and chatted, thats cool and I got the job. Its when I have to stick the old suit on and its all formal sat accross from them that I get it.[/quote:c7e26d7245]
oli - if you want my advice man, don't talk. seriously!
just answer the question when you are required to answer, then turn it around and ask them a question related to the company or them, that would make them feel better. this of course requires you to do some research into the company (about 2 or 3 hours should be enough). write down the questions you plan to ask on paper and take it along with you incase you forget. also, bring a notebook and pen as you may need to take down details.
in an interview i had a month ago, i let the 2 interviewers speak and all i did was occasionally nod, or said "uh huh". when they'd stop speaking i would ask a question relating to how they saw the company going or what they felt would be the biggest task to overcome. in the end, the interview went on for two and a half hours and my part was perhaps just two minutes. i was offered the job after just ninety minutes through the interview.
as for nerves, don't worry too much about this. i suffer greatly from nerves, even when i'm talking to people i know. i'm just not good at talking to people in general - geeky introverted web designer idiom, etc

most good interviewers will acknowledge the fact that people are nervous when they attend interviews - it's natural! a good tip is, if they offer you a cup of tea or coffee, say yes please guv'nor! that way, in nervous or tricky moments you can always take a drink to gulp and also you have something to hold if you start getting shaky.
try to act confident, even when you're not. after a bit of practice, by pretending to be confident, you will gain confidence!
i have more advice if you need it but i don't wanna say too much as sometimes when you give people too much information they get overwhelmed. (not that you seem dense or anything!)
anyway, good luck with the interview, and i hope you get the job
*prole's disclaimer* - prole accepts no responsibility for people that use this information and do not get the job 8)
ps when they say "do you have any questions", never ask about pay as the first question! wait til they start discussing it.