Special Note: the following advice is based on our preferences and are opinions based on our experience.  Remember, our word is not carved in stone... after all, it's your silver! 
Can I put my sterling and silverplate in the dishwasher?
Yes, but please don't. Sometimes the heat in the dishwasher causes knife handles to come loose. Everyone's situation is a little different, but basically the chemicals in your water can combine with the chemicals in your cleaning agent to cause discoloration and loss of oxidation. (We can usually tell if silver has been cleaned in a dishwasher).
What about dipping my silver to polish it?
We have two problems with using dips: 1) it removes the oxidation (see next paragraph) from the pattern, and 2) if not thoroughly cleaned off, the dip leaves a coat on the silver that tends to discolor over time. Our advice? Use a dip to clean very tarnished fork tines, then thoroughly hand polish and wash. It saves you some elbow grease, doesn't remove the oxidation from the pattern, and the dip chemical is removed from the silver, avoiding discoloration problems.
What's the black stuff around my pattern?
This is called oxidation and it sets off the pattern design. In recent years, manufacturers have stopped oxidizing new pieces, although it was standard practice in the past. We find oxidation on pieces highly desirable and place more value on pieces with good oxidation. This is yet another reason why we do not recommend using silver dips to clean your silver, being that they remove oxidation. Instead, we recommend using silver polish. The illustration below shows just how much of a difference in appearance there is between an oxidized and non-oxidized piece. You can see why our preference is the oxidized version...
Non-oxidized pattern design
Oxidized pattern design
If some of your silver is lacking oxidation and you'd like to try to restore it, we recommend having a professional do the work. If the silver has been dipped or put in a dishwasher, the residue left behind will prevent oxidation from forming, thus making it highly difficult to restore.
OK, so how do I take care of my silver?
Wash your pieces in warm sudsy water. To polish, get a good silver polish (we use and recommend Wright's, but many other brands are suitable), polish piece by piece, then hand wash and dry. How often you polish depends on how you store it, how often you use it, etc.
Monograms - leave them or remove them?
We avoid pieces of silver with monograms removed. There will be a "dent" or bend in the reflection of a piece that has had the monogram buffed out. There's always a danger that some of the pattern design was damaged when the monogram was removed. And, as a work of art, many of the old monograms could not be easily replicated today - the art has almost died.
How do I judge condition?
You look the piece over very carefully, in good light. For flatware, look at the utensil part of the piece, front and back. Are the fork tines cut, heavily scratched, bent or twisted? Is the spoon bowl worn down on the edges? Is the knife blade bent, scratched or pitted? Do any pieces have 'pits' (little dark spots) in the utensil area? Look at the handles - is the design crisp and sharp? Most important: do the pieces look like they'll fit in with your set nicely? When evaluating hollowware, look the piece over carefully for breaks, cracks and poor repair jobs. When you come across a piece at a shop or show, contain your excitement long enough to really evaluate the piece. Even seasoned buyers have trouble with this!