Seven years ago, I planted 25 asparagus root crowns in deep trenches in a bed running the length of my garden. The first couple years, we let the plants develop and harvested nary a spear, but a few years ago, we started getting so much asparagus that we would give it away to anyone who expressed the mildest interest. While we still give a lot away, we've developed a system for preparing and preserving this spring bounty so that we can enjoy it year round. You can use this method with your own garden's bounty or what you pick up at farmers' markets.
Start by setting a large pot of salted water to boil on the stove and filling another pot or kitchen sink with ice-cold water. While the water heats up, cut the tips off the spears (the top 2-3 inches) and set them aside. Cut the stems into 1- to 2-inch long pieces. Place the stem pieces in boiling water for a minute or so, just until they turn bright green. Remove from the water using a slotted spoon and immediately transfer to the cold water. Stir to cool the stems completely, then spread in a single layer on a rimmed baking sheet. Place baking sheet in freezer for four hours, then transfer frozen asparagus to zip-top freezer bags or freezer boxes. Cooking food in boiling water briefly is called blanching and cooling it in cold water is called shocking and I find the combination of techniques useful for preparing many spring and summer vegetables either for freezing or fresh eating.
You can prepare the tips the same way, especially if you want to include them in a salad, or you could just blanch, roast, stir-fry, grill or prepare them however you wish. The incomparable taste and texture of asparagus tips are best appreciated when fresh, but the frozen stems make fine additions to soups (especially pureed potato-leek soup), twice-baked potatoes, stir-fries, casseroles, and quiche.
If you like pickled asparagus, try putting up some yourself. I'm currently experimenting with lacto-fermenting asparagus and will share my results!