one of my all time favourite brand is Liz Lisa. I love their style, the cut of their clothes and their colours. What I do not like is their price. But it doesn't have to be expensive at all, except you always hunger for the newest collection and want it now. If you have patience and also buy items from the past collection it's not that expensive anymore.
1) Tokyo kawaii life
This shopping site offers the newest Liz Lisa items. But they also always have a huge sale section with most items being about 30% cheaper.
The older collection can be found in the outlet with items up to 70% off. link
Tenso that is no problem at all.
This site is a shopping service which lets you bid on auction sites like yahoo japan. Now second hand items is a huge business in Japan and due to lack of big closets Japanese women tend to sell their old clothes.
Liz Lisa can be found in the RI category:
More about that here.
3) Second hand groups
Livejournal was THE site but everything changed when facebook took over.
Search for cheap items at the liz lisa sale group or at the gyaru sale group.
Shopping tip: buy locally! If you live in Europe, try only to buy from European sellers. This has two reasons: cheaper shipping and no taxes.