Excel Reading in background Process (i.e using windows services)

Question

I have a Excel file that is not in a table format
i want to read the required data from that excel file in the background (using windows service)and store it into sql database
Excel data would be like this
151601 ,151602 are the two records
i want to read some of the data from each recrod
this is sample excel file.this excel might have thousands of records like this
 

151601		464855166	xxxxxxx, xxxxxx			10/2/1976	6/1/2009 9:18 AM		xxxxxxx,xxxxxxx
						xxxxx		xxxxxxxxx
	xxxxxxxxxx:	xxxxxxxxxx						xxxxxxxxx	31481
	xxxxxxxxx	xxxxxxxxxx						xxxxxxxxx	xxxxxxxxx
	xxxxxxxx	xxxxxxxxxx						xxxxxxxxx
xxxxx				6/1/2009 at 09:34 AM (DMP)		85025			0.00		21.72
xxxxx				6/1/2009 at 10:04 AM (DMP)		85652			0.00		6.50
xxxxxxxxxxxxxL*				6/1/2009 at 09:57 AM (DMP)		80053
151602		456840093	xxxxxxxxx,xxxxxxxxxx			11/13/1948	6/1/2009 9:20 AM		xxxxxxxxxx,xxxxxxxxx
	xxxxxxxxxx:	xxxxxxxxxx						xxxxxxxxx	xxxxxxxxx
	xxxxxxxxx	xxxxxxxxxx						xxxxxxxxx	xxxxxxxxx
	xxxxxxxxx	xxxxxxxxxx						xxxxxxxxx
xxxxxxxxxxxxxx*				6/1/2009 at 10:00 AM (DMP)		80053

please help me
thanks in advance.