Yeah, about orchestration I can recommend you "The Study Of Orchestration" of Samuel Adler. Exists only in english, but as far as I understand you're from the USA. The book is in my opinion one of the best about orchestration, instrumentation available nowadays! And the good thing is that it contains also CDs with sound clips to the given examples and videos (about specific techniques on individual instruments) and if you have enought money and time then there's also the "Workbook" with tons of exercises to develop your skills and technique in orchestration/instrumentation.
Check in Amazon, I think in USA it might be even a little cheaper than here. The CDs (they're around 5 or 6) must be purchased seperately from the book.
I think it's the best one you can get, exactly because of the fact that it has sound and video samples makes it much more effective.
It will also give you answers to your question how to achive such a lush and rich string part.
Otherwise there are also other good books like Hans Kunitz "Instrumentationslehre", they are around 13 single books for each instrument/section. But it has never been translated from german. Or Richard Strauss/Hector Berlioz "Instrumentation" is a fantastic book but a little old fashioned, stuck a little in the late romantic periode, instead Samuel Adler's "Study Of Orchestration" shows also modern contemporary instrument techniques, though he puts focus on traditional orchestration from baroque, classic, romantic, impressionism to 20th century literature (Stravinsky, Schönberg, Bartok, Webern, Penderecki and more american contemporary composers than european ones)
Good luck!
Andie