US Post Office

Are you ready to dish out money? I hope so because postal costs have doubled since I last sent an international parcel and that was only 6 months ago! They are less reliable than UPS or Fed Ex but I have found that if you try to ship from their stores you could be paying 3 times as much!
One of my first holiday priorities is getting packages out before the madhouse begins around mid Dec. Sure they are understaffed these days so expect long lines. I try to make it a point to review everything with them because I know getting my gift to my recipient means a lot. I am only rating this particular location because they are all the same no matter where you go.
Some of the Post Offices offer passport services. They do sell mailing supplies but you are better off going to a discount store to get what you need.
The most important thing I must stress when you are mailing a package is to make sure you get tracking and insurance depending upon the value of your item. This is especially true when you are shipping international including Canada. One may think that Canada is not so far away but guess what? It is a international and is treated as such even though it borders the US.
Tracking has saved me and my recipients on a number of occasions because if you just use the customs form then there is no telling where your parcel will end up once it leaves the US. Tracking has helped me in the past start case investigations and the Post Office has internal scans that can see where a lost parcel went.
Yes they are running low on your favorite holiday stamps for now. But I am sure they will get new ones in if you are planning to send cards.
Domestic shipping gives you more latitude because it normally includes tracking. Everything is based on weight not distance. Keep that in mind when you are packing your gifts. Although it is not the best way to send packages it still is cheaper than using UPS or Fed Ex.

I have visited this post office multiple times to drop off packages for which I already bought postage online. The post office is small and looks sort of run-​down. The one postal employee who works there is behind protective glass, which makes me feel a bit scared to be standing in line without protective glass myself. She is always nice and thanks me for my business. I do not usually have to wait in line long before I am served.
2015 UPDATE: I continue to visit this post office. The employee there always does a good job. Unfortunately, when I purchased certified mail, the post office on the other end in another state delivered the envelope as regular mail rather than certified mail. I paid several dollars for nothing.