Curiosity about Biotechnology/Molecular Biology Patents

[merlin]

There is no mention in any of my molecular biology textbooks
(Watson et al, Lewin, Kornberg, Singer & Berg) or in most of
the journal articles I read about patents which may restrict
the use of particular techniques or materials to produce any
specific result.  How are researchers supposed to know about
the existence of such patents absent so much as a hint there
may be a patent covering standard published techniques?  

As an example, I am informed I can only use a Taq polymerase 
sold as part of a PCR kit (which includes a license for PCR)
with a licensed PCR thermal cycling device (Perkin Elmer) --
or Hoffmann-LaRoche could sue me for infringing some patent.
I was considering using Taq from other sources -- so I would
really like to know -- how does one avoid infringing patents
without consulting an attorney every day about project plans?

It seems to me the increasingly large number of broad based
(perhaps too broad) patents may tend to inhibit innovation
rather than fostering scientific progress.  What do the far
more experienced researchers in this newsgroup think about
the issues of notice of patents and their inhibitory effect?

Thanks, AJ Annala

Ph.D. Candidate
Biological Sciences
University of Southern California