Hi Libby
I expected others on the forum would have all the information you needed. I only know bits and pieces. His collection, called the "Plasticarium" is located on the rue Locquenhien in Brussels. The postal code for that part of Brussels is 1000 and I guess that with that address your letter would arrive. The street in question starts at the canal just north-west of central Brussels and is not that long so...
Mr Decelle does not live there but his phone number is international+32 2 344 9821 if you are outside Belgium inside it is 02 344 9821.
Sorry for being so sketchy and late..
or have a look around...
or have a look around this extensive site and find an interview with Philippe Decelle, complete with address and phonenumber. Good luck.
tilanus
http://www.designaddict.com/exhibitions/decelle/interview.html
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