Is there some website or webpage that allows you to quickly see whether a particular microarray platform has probe sets against your gene of interest. I would be interested in finding out various Affymetrix, Agilent, Illumina platforms, and also for exon arrays. I know you can find this out from the annotation files made available by each provider separately, however I was wondering whether there was any company-independent source for this information.
Why not just use Ensembl biomart, enter your gene ID and select the probesets you're interested in under Attributes/External
This assumes that you're interested in the (limited) number of platforms provided in BioMart.
Do you have a particular reason why you are avoiding company-dependent information?