Tech stocks are plummeting, bankers are warning venture-backed companies away from IPOs, and many are convinced that we’re heading into a recession. But start-up companies, the little babies of Silicon Valley, have no cause for fear, because the tech grand-daddies — Microsoft, Cisco, IBM — continue to be bullish about dealmaking.

Their capacity for huge acquisitions, like Microsoft’s bear-hug offer for Yahoo, may be limited, but these cash-rich tech titans love to buy lots of small companies that take them to new markets or make sense for their corporate strategies. At a Redwood City venture capital conference today, executives from across the tech spectrum, including Microsoft, Cisco, News Corp’s Fox Interactive Media (which owns MySpace) and McAfee, said they remain gung-ho on acquiring start-up companies. The worsening economy hasn’t changed their attitude, it seems — two months ago, at another VC conference, they said the same thing.

Cisco dealmaker Rob Salvagno said the company has made between 10 and 15 acquisitions every year for the past few years, and he doesn’t see that changing this year. They’re going to keep up their hunt for the coolest start-ups in international markets as well, he told the crowd.

Fox Interactive Media’s Jack Kennedy said they were more opportunistic about buying companies, but are energetically prowling for “game-changers”.

And if you thought Microsoft’s eyes were trained solely on Yahoo, think again. Dan’l Lewin, Microsoft’s head of emerging business development, said the company will do “a lot more of what we’ve been doing,” which is, picking up about 20 companies a year.

Separately, Ebay’s M&A chief Lorraine McDonough in a chat with Reuters, said the Web auction giant has the ”financial flexibility” – meaning about $2.4 billion in free cash flow — to pursue attractive opportunities this year.  Ebay, best known for its buyouts of PayPal and Skype, will continue making targeted acquisitions, she has said before. For start-ups, obviously things are still green in the Valley.