Hi friends, got a question about equipment

That's a really open ended question.
I am quite happy with my MXL 990/991 mic package, but others don't like them. Mic choices can be highly subjective.
Do not get a mixer or mic that uses a USB connection. These will introduce a second interface, and will defeat the superb performance of your E-MU card.
At a minimal investment, the Behringer Xenyx802 will make a decent front end for you.
Check the specs, and get the best you can afford.

I spent an hour trying to find specifications  of EMU 1818, no success. Then I tried to find information about APRO 500, which is a vitamin pill. A-500PRO would be a keyboard, which I suppose is what you are using :o)
But still..

Does 1818 not have phantom power? Anyway, Shure sm57 is a dynamic mic, which can't use phantom, only condenser mics use phantom.

I don't understand why you would need a mixer? It may be handy sometimes, but if you're on a budget, why spent money on that? You're not recording vocals and bass at the same time, are you? Also, you're not telling if you're micing an amp or recording directly into SONAR. 
Are you working alone or recordintg a band?
 
Depending on the 1818s inputs, it may be you need a pre-amp for the bass.
I don't know what's your definition of "high quality", but as the only mic sm57 is usable, but maybe not very high quality for vocals.