The 40%-off sale at Quest (coming in a few days) is definitely a good break on prices, but if you factor in their shipping costs you will need to order quite a bit of stuff just to break even, let alone see much savings.
If there are Hobby Lobby stores near you, watch their web site for the 40%-off coupons that they run every 3-4 weeks. You can print as many coupons as you like. HobLob stores seem to all have a pretty good stock of Estes stuff, including motors.
Less often, but still worth watching for, are similar discount coupons for Michaels craft stores and Jo-Ann fabric stores. Michaels seems to put coupons in the newspaper for most major holidays. Some Michaels stores have a small rocketry section, some have nothing at all (Michaels seems to be getting out of the model rocketry biz). Jo-Ann also puts the occasional coupon in the newspaper and while they do not carry model rocketry stuff (at least, in my town) they do carry balsawood that you can use for fins and glider wings.
In some parts of the country, Target stores apparently carry model rocketry stuff in the toy section, but I have not seen rockets/motors in a Target in a long time around here. Likewise, Toys-R-Us used to carry a small rocketry section but not anymore.
Check your local hobby shop. It never hurts to ask. However, expect their prices to be a bit higher---
And there are TONS of new mail-order vendors in this hobby since you were younger. Almost ALL of them are great, honest, knowledgeable, fast, and great (I can't think of even one to warn you against). They are involved in rocketry because they love it, not because they plan to make a killing. If you like, check here on TRF about any specific vendor and you will almost always get useful feedback. The "Big E" is no longer the only game in town for fun kits, and quite often, does not even offer much that you will find interesting. Our new vendors, OTOH, offer a wide variety of great kits, ideas, configurations, skill levels, and performance levels. The only problem is that there is soooo much to choose from that it almost gets confusing. Start at Applewhite, go through the list to Zooch, and enjoy everything in between.