Yes, certainly harvest your own fresh lavender for baking! I use it extensively in sweet and savory dishes.
I refer to buds as the unopened blossoms on the lavender stems. These are what are harvested and sold in bulk at many natural foods markets. Just pick a stem or two, shake off any bugs, then hold the stem over a plate or bowl to strip off the buds with your fingers. You can dry the stems before stripping off the buds if you like. Store extras in a glass jar with a lid. Enjoy!