What association does Laurence Myers have to David Bowie? And
precisely when was this association active?

Dear Collin Superhero, 

In 1971, Laurence Myers was a manager of a recording company, with
which David Bowie, had a contract according to his own bio
http://www.laurencemyers.co.uk/profile.htm and according to a Bowie
newsgroup "On August 1st, 1971, a recording contract was signed
between Gem and Bowie. This contract gave Gem the rights to Bowie's
recordings for five years. Gem was owned by Defries and accountant
Laurence Myers". <http://groups.google.com/groups?selm=3ACBECF7.1A7CF9A6%40home.com&oe=UTF-8&output=gplain>.
Since Myers left Gem in 1972, that's probably their connection.

Search strategy: "Laurence Myers" "david Bowie" 

Further Sources for you:
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&group=alt.fan.david-bowie

I think that answered your question - but if you need any
clarification, please ask. I'll be pleased to answer before you rate
the question, and save the world with your superhero powers.