You could also try the Public Analyst nearest to your uni. There are 32 accredited laboratories around the UK and you can locate your nearest on the following website:
http://www.publicanal...the_laboratories.html
At first glance, you may not think that a Public Analyst placement would be ideal, but I'll point out that that virtually all of them employ chemists, microbiologists and other specialists that often have a forensic background themselves. The laboratories all carry out analysis to forensic science standards.
I've known quite a few students who have gained valuable experience of in these laboratories. Some of these laboratories are run by local authorities and others are operated by private companies so there's quite a lot of scope here to try to get a placement.
One company I'm familiar with is Minton, Treharne and Davies:
http://www.minton.co.uk/
Click on "Forensic Investigation" on the sidebar for further information although all the website pages are worth a glance.