I pursued an agent for a novel, while I pursued publication (for a novella that was unrelated to the novel) with small publishing houses. It took slightly longer to find an agent than it did a publisher for that particular project. The problem was that small publisher then folded in under a year of publishing my little novella and I only had about 50 sales in that time.
Small publishers *can* be easier to find, but they are not always stable. The good ones will not be easier to gain publication from than finding an agent to rep you. And a reputable agent will give you a shot at bigger, better paying and more stable publishers. There is also nothing to prevent you from moving on to publishers if it turns out that agents are not interested in this particular book. (And, yes, you will have spent time looking for an agent, but the advantages to having a reputable agent far outweigh the minor setback of not being published as quickly.)
Also, I'm never a fan of starting at the bottom when looking for a home for a project (which is basically what the advice about small publisher over agent is telling you). Not every project is destined for the big houses and best seller lists, but better to try for the best option and naturally find where a specific work fits best than to jump to the easy sale first and later regret it.
Just my two cents. Best of luck.