Need a Macro or Formula Solution for Excel 2003

I am trying to develop a formula or macro for an Excel-based application. i went the formula route but Excel 2003 only allows 7 embedded formulas within a formula and I need more than that.

Here?s what I?m trying to do.

1. Have the program go the highest value cell in a string of cells.
2. Test for a value greater than zero
3. If value is greater than zero then show value of that cell, if not, go to the preceding cell and repeat the process.
4. Need to do this process for an indefinite string of cells.
I developed a formula which works by embbeded formulas, but only for seven iterations because excel does not allow me to embed more formulas.

I need either a formula solution or maybe a Macro that would do the job.

Thanks.