I recently wrote this post about accumulating coupons. One thing I would like to elaborate on is the coupon train. I LOVE it! I signed up with my coupon train through Yahoo here.
The way it works is there are six people assigned in each group and each is assigned a letter and a number (A1, A2, A3, etc). You have access to the names and addresses of the people in your group and other groups as well. You send an envelope of any excess coupons to the person ahead of you in the coupon train. They take what they need, get rid of any expired coupons, add any of their coupons that they won't use and send all the coupons to the next person in the train who then does the same. There can also be multiple envelopes going throughout the group at once. So for example, A1 can send to A2 while A4 is sending to A5. This keeps the coupons rolling in all the time. I have been a part of this since August 25th and have already received at least 4 envelopes from the person behind me and have been amazed at all of the great coupons. She even asked me for a wish list - which was so sweet!
The other cool thing is that in my group, there are people from all over the US. Many times the inserts are different in different markets and I have seen some great high value coupons that I would not have had access to before.
If you are looking for a way to build your stash of coupons, I highly recommend the coupon train. You won't regret it!