for sun to part sun, there are several spiraeas with yellow to chartreuse foliage. 'goldmound', 'goldflame', 'magic carpet' are some. see the link below.
for a more shady spot, the cultivar 'little honey' is a more dwarf form of the native oakleaf hydrangea with yellow foliage that matures to chartruese. you will probably have to order this one as it has not reached the box-store garden center markets yet, that i know of.
here is a link for that one:
http://www.hydrangealittlehoney.com/images.htm

Here is a link that might be useful: spiraeas

There are some chamaecyparis that stay gold like sungold. Chose the brightest ones. I have 3 that are very yellow and one that is greenish. It was a little green when I bought is and it hasn't gotten as yellow as the others.
Also, there is the smokebush, golden spirit that has stayed chartreuse. Scottsdale Farms had them.
The tiger eye sumac is doing well but is deciduous.

Thanks Steve, because i want Golden Spirit and Tiger Eye sumac!!

I have Ogon Spirea. Taller than your desired height and decideous but it's beautiful and golden from late winter to late fall.

Beautybush 'Dreamcatcher' and Fullmoon Maple