Jeepers, Chuck. First thing you need to do is call the previous homeowner, and have her go through care and maintenance of this little grove. She certainly should have given you a tour of the grove, the drip system, her fertilizing system, products, timing, pest management system, etc. Write everything down in detail. Write all your questions down ahead of time, then make sure as she reviews everything, all YOUR questions are also answered. You say this previous homeowner really knew what she was doing, so tap into that. Then, I would call the UC RIverside Extension office, and see if you can speak to one of the extension agents. I'd refer you to Tom Shea, but I believe he is no longer working for UCR, which is really too bad. Another great resource is the San Diego County Master Gardeners. They can assist you to some degree, or at the least, put you into contact with someone who can guide and advise you (back to the UC extension folks). Lastly, the UC Davis Home Orchard web site is very helpful. I will give you a few links that will provide you with basic info, but it's your previous homeowner who can give you the exact details of their orchard. (If these hyperlinks are broken, simply copy and paste them into your browser window):

http://homeorchard.ucdavis.edu/files/140618.pdf

http://www.mastergardenerssandiego.org/downloads/citrus%20for%20home%20garden.pdf

http://ucanr.edu/blogs/slomggarden/blogfiles/4260.pdf

http://ucanr.edu/sites/sacmg/files/115406.pdf

UC Davis Advanced Avocado and Citrus Training Classes (closest is Riverside, HIGHLY recommend attending):
http://camastergardeners.ucdavis.edu/?blogpost=9519&blogasset=4537

http://homeorchard.ucdavis.edu/Fruits_&_Nuts/Citrus/

UC Master Gardener Handbook:
http://anrcatalog.ucdavis.edu/GrowingVegetablesFruitsNuts/3382.aspx

Integrated Pest Management for Citrus (this is from the ANR Catalog, several other very helpful resouces for citrus available, just search by "citrus"):
http://anrcatalog.ucdavis.edu/IntegratedPestManagement/3303.aspx

And this site should be bookmarked for info about citrus varieties. Sadly, I think it's too late for you to squeeze into the UC Riveride Citrus Variety Collection Citrus Day, which is being conducted tomorrow, but definitely something you'll want to consider attending next year, as they provide great presentation about citrus care:
http://www.citrusvariety.ucr.edu/index.html

And lastly, the Sunset Western Garden Book and the Sunset Western Garden Book of Edibles.

Patty S.