As a small business owner who started his business only 6 months ago, I see your dilemma.
I used to ask myself similar questions all the time. People came to me with what seemed to be fantastic offers for advertising on national television, radio, newspapers, etc... and I found it really hard to take decisions. I call them shiny objects and it is so hard to resist the temptation to jump on them
Until I followed a friend's advice and drew up a marketing plan for the next 6-12 months.
It helps a lot, even though it constantly changes, it gives you something to fall back on. It enables you to determine a budget and track the results (you set goals for every activity you do). We asked ourselves two really helpful questions when we were creating the plan:
1) who are my target audience and where are they? - this eliminates a lot of those shiny objects (no use for a cheap ad in a national newspaper if you are targeting local customers)
2)am I going to reach this audience more than once? I do not spend money unless my marketing efforts have a chance of reaching the same target more than once. - again, a lot of shiny objects fail this test.
Having a marketing plan really makes my live a lot easier