VLookup question

To anyone who can help... I'm using the following formula

=IF(B7="","",INDIRECT("'"&VLOOKUP(B7,lookup!$A$2:$ B$32,2)&IF($A7>=$H$3,"'!E3",IF($A7>=$G$3,"'!D3","' !C3"))))

For whatever reason, the last IF formula doesn't seem to work. A7 represents a date and G3 represents a date to compare with A7. In a sense I want this formula to be able to go to a worksheet via the VLookup function and then compare the two dates in H3 & G3 from that particular sheet with that of another sheet, specifically a date in A7. Everything appears to be working except for the later IF formula portion...It wants to always keep D3 even though the date in A7 may be less than D3. I've attached a zipped file of a smaller version of what i'm trying to accomplish with comments inserted as well. The cells won't exactly match my formula above, but it will be a similar formula. I'd sure appreciate anyone's help in this matter. Thanks in advance!