Yesterday I stumbled onto something really great and I just wanted to share. 

Our son Ethan got a sudden growth spurt and we woke up to find that none of his clothes fit him anymore.  In the old days, I would just run out to Old Navy and

• Thrift stores--Thrift stores are usually run by nonprofit organizations who accept items by donation.  Thrift shops will often have a section just for clothing.  If you go to a thrift store several times at different times of the week, you'll find that some days to shop are better than others and that some thrift stores are better than others.  I have found that shopping on Thursdays or Fridays are better than the weekend or the beginning of the week.  Weekends are often high shopping days (when all the 'good' items go fast) and Mondays are the days that things begin to get restocked. 
• Consignment shops--Consignment shops have clothing that a shop is selling for individual people.  You can bring your children's clothing that  no longer fit.  If the shop is able to sell the clothing, you will get the money (less a small fee to the store).  The consignment stores have high standards for the clothing they accept so this is a great place to find name brand clothing for only a couple of dollars.   
• Community consignment sales--This the end-all, be-all of great deals.  Churches and area community centers will often hold these sales twice a year (in fall and spring) specifically with children's clothing and toys, strollers, cribs and everything else you could possibly need.  This is such a great resource for first-time parents as well.  We went to several of these sales yesterday and walked away with a double stroller for only $30.  What a bargain. 

If you are looking for consignment or thrift stores in your area, just go to www.google.com and type in your city name and consignment or thrift.  You can also check community websites (such as craigslist.org) for sales in your area.

Good luck!