I've looked for this information myself in the past. I found three methods that were most helpful:
(1) Yahoo Finance, the main page will often cover acquisitions of the day. They also have Investing Ideas along the left margin half way down that tend to focus on acquisitions.
(2) Nasd100.com is a cool stock ranking site that ranks stocks daily based on various factors, one of them was Acquisitions or News Related Momentum if I remember correctly.
(3) Type in April 8, 2011 Acquisition Press Releases at Yahoo and Google. They will list all press releases for today that relate.
(4) PRNewswire.com, a press release site that you can search for acquisitions in by the date.
Hope this is helpful and best of luck!