The first thing I would say is: "It's not the end of the world."
Take some time to grieve your loss and then decide what it is you really want to do. Sometimes getting fired is the exact impetus it takes to get someone to leave a job they were never really happy with.
Ask yourself: If on some level you quit before you were fired.
If your former employer was a large company most HR department's common policy is to only tell prospective employers your date of hire and when you left the company. Very few large companies give out details regarding the reasons why you're no longer there.
You can tell all prospective employers you had saved some money and decided to resign in order to seek a different type of a position rather than put in a "half-hearted effort" at for your former employer.
Naturally you would list only references who would give you a glowing report. Another common tactic is to say your former company had a round of layoffs. Never state you were fired on any job application!
Only the rich and famous can get away with being fired without having any stigma attached while being considered for new jobs.
Apple once forced Steve Jobs out of office. Presidential candidate Carly Fiorina was fired from Hewlett Packard, NBA and NFL coaches get fired by one team and hired by new teams. Howard Stern as well as other celebrities have been fired or had shows canceled.
It's not over until (you) say it's over.
There are some things that can make it more challenging however.
If you were at the last company for several years, you're over the age of 45, you're unwilling to network, or try doing some things outside the box. Whether that means dying your hair, signing up as a temp, willing to accept a pay cut, try a different industry, or even starting your own business. Don't stay at the "pity party" too long.
You're not the first person no are the last person to ever be fired! Keep knocking on doors until you get a yes.
Every ending is a new beginning!
'If you really want to do something, you'll find a way. If you don't, you'll find an excuse.' - Jim Rohn