While it’s tempting to go through clip art catalogs and select an image that you think could work for your logo, I don’t recommend it.
I understand that clipart catalogs offer a wide array of ready-made art pieces, that often look quite good, and it’s easier to choose a final piece of art than to work with a designer. Especially since, when you work with a designer, it’s a big leap into uncertainty – you never quite know what you’ll get from a designer.
But, you’d be doing your business a big disservice if you choose a clipart piece to use as your logo icon, because you won't have exclusive rights to it. That means that anyone can use that image in any way that they want. So, other companies could use it as their logo, which would take away from your uniqueness, lead to you being confused with other businesses, or it could even lead to you looking like a copycat and being accused of logo plagarism.
Imagine if your logo clipart is later released as a part of a Microsoft library, and is suddenly then used in business presentations of all types!
Or, other businesses could use the clipart as an illustration, which could have the same effects. If a large corporation buys the clipart to use in a major ad campaign, you’d wind up with a whole cache of problems.
Anyone else could also use “your” clipart in a negative way – which would then have a negative impact on your company's brand identity.
A clipart logo would also not be something that you could own the full rights to – and it would be impossible to copyright or trademark.
A good use of clipart would be to review some clipart libraries when you’re first talking about your logo with your designer, and to use clipart that you like to communicate your visual tastes to your designer.