I have to agree with Space that the Japanese greens are wonderful, but there's a lot to be said for the Chinese greens also. Since you have already ordered from TeaSpring, you may want to go back and get a variety of samples with the thought of seeing what does suit your fancy. They have an especially good rep as green tea specialists.
If low price is an important part of your objective, Jing Tea Shop has low-price "everyday" teas: http://www.jingteashop.com/cat_ev_green_tea.cfm
Yunnan Sourcing also has a very inexpensive green that I have enjoyed:
http://cgi.ebay.com/500-grams-Mao-Feng- ... dZViewItem
Of course, you may or may not share my preferences; tastes vary quite a bit especially in the greens. If you are interested in a good quality sencha at a lower price, I would have to suggest Adagio's Sencha Premier or O-Cha's Everyday Sencha. The Adagio product struck me as more fruity while the O-Cha seemed more grassy, but both good and attractively priced.
Also, at this time of year you have to remember that the new season of greens will be out in just a few months depending on weather, so don't overstock on last year's harvest. Last year the Chinese greens started coming out in March, earlier than any previous year.