using a tripod and/or monopod can improve photos for only a small amount of money
just getting to know you camera really well is something that really helps, but that only really comes in time.
i find that you can usually improve a good shot by editing, fiddle with the levels and unsharp masking can make a big difference
thats a lovely shot by the way though
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hope you don't mind, but to show you what i mean:
you can see the difference that editing makes, and that was done by a complete amateur with software i got free on the internet

(GIMP 2)
(for comparison, i'll repost the original

)