go used:

check out traditional archery classifieds on different sites, including this one.
On one there is a inter-nature takedown recurve for $185 45lbs and a bear "Blackbear" for $100 its 45lbs ...these are two that i noticed on the first page.

ebay is Good for used but kindof trickey because depending on what you type for your search youll leave out some results...so youll have to know Brand names sometimes.

longbows are kindof pricey from custom makers, forwhateverreason and harder to find in the lower pull wieghts.

if you want a good longbow at aMedium (250-500)price brand new check out Martin archery, Bear. you cant go wrong with either company. and they are american made.

Inter-nature(korean) Makes a Longbow called the Viper that you can get new for $225 or so. you cant really go wrong with it either its actually a nice bow for the $.
you can get a cheaper price than these guys....but they have a nice description heresthe link. http://www.oldbow.com/viper_longbow_ss_1.htm