Yapta, an online travel shopping service, has raised another $2 million in Series B funding led by Voyager Capital.   Also joining the round were Bay Partners, First Round Capital, Swiftsure Capital, W Media Ventures and other private investors.  This brings Yapta’s total capital raised to $7.7 million.

The Seattle-based startup addresses the issue of fluctuating travel prices on the Web.  For example, one day a flight to Vegas may be offered at $150, and the next at $75 and so on.   Unlike other competitor sites, TravelZoo and CheapTickets, which offer users deals on flights, Yapta monitors airfare price volatility and alerts consumers when prices on their selected flights drop via email alerts.  To make things better, if a customer buys a ticket, and the price on that ticket drops further, Yapta offers travel vouchers and in some cases, cash refunds.

Based on surveys conducted by American Express Travel in May of 2009, 89% of travel agents report receiving more inquiries about deals this year than in past.  Yapta says its users are more “self-reliant and confident” when using their website since they have access to pricing in a historical context.

In hard economic times, startup companies must have some sort of business model to be worthy of funding.  In Yapta’s case, it generates revenue through targeted advertising for the travel industry.  It also has a Premium Service for people who don’t feel like waiting in line or making the effort to receive travel vouchers.  Yapta will take care of this for a fee of $15.

Yapta, which was founded in 2007, says it has alerted hundreds-of-thousands of travelers to more than $150 million in travel savings. The company will use this round to grow these stats by furthering the development of its airfare and hotel price monitoring service and provide working capital for the company’s continued marketing efforts.