How to count how many purchases I get a day, Counting number of times a date repeats.

Alright so I have an issue I am trying to figure out and have had no luck for the last week. I am a developer and make apps for many different mobile platforms. I get a report each month which has a list of the time and date a purchase has occurred. My question is how can I go through the data and put together how many purchases I get a day. Below is what I have and what I want to get returned. Column A are the dates purchases occur, column B are the dates for the length of time I want to look at and column C are the amount of purchases I get per day. Some days I get 0 purchases some I get 3. Now the below data is just an example I have data from 4/19/2011 till today 2/2/2012. I need to do this because I would eventually like the make a bar graph from that time frame to see graphically how many purchases I get each day. If any one can help me out to find a formula that will work to do this it would be SOOOOO helpful. Iv looked everywhere and have had no luck. Thanks in advance if you can help me out! I also attached the spreed sheet if any one doesn't understand what I am trying to do.
January 2012 - Report.xls

A B C
1/31/2012 1/31/2012 1
1/30/2012 1/30/2012 1
1/28/2012 1/29/2012 0
1/28/2012 1/28/2012 3
1/28/2012 1/27/2012 1
1/28/2012 1/26/2012 1
1/27/2012 1/25/2012 0
1/26/2012 1/24/2012 1
1/24/2012

=COUNTIF(D:D,"="&DATE(2012,1,31)) works if you figure out a way to remove the time from the cells.

Alright I tried that formula and It did not work. Column A I formated so it is only shows the date and not the date and time. When I copied it down the column it just shows 0 all the way down. I have data like the example above from 4/19/2011 till today 2/2/2012. Thank you for the help but ya still doesn't work. See the spread sheet too if you don't understand what I am trying to do. Any way thanks again for the help, I hope I can figure this out!

@Marcol, Thank you so much this is exactly what I want. I would how ever like all the dates in table 1 & 2 and if there are no purchases Id like there to be a 0 there. I'm going to look through the formula and try and figure out how it works. If you could let me know how to go about getting all the dates to show up there even if there isn't a purchase?