finding nested element

In my attached code sample, I have added an ID to a particular HtmlDiv called "THIS_TEXT". In a coded step, how would you go about finding that particular div if the ID was not added? I have something like this currently:

HtmlDiv divContainer = Manager.ActiveBrowser.Find.ByAttributes<HtmlDiv>("class=x-grid3-row-first");

HtmlTable table = divContainer.Find.ByAttributes<HtmlTable>("class=x-grid3-row-table");

// Fails on step above: Object reference not set to an instance of an object. Am I missing something?

IList<HtmlTableRow> tableRowList = divContainer.Find.AllByTagName<HtmlTableRow>("tr");
string returnValue = String.Empty;
for (int i = 1; i < 2; i++)
{
   returnValue = tableRowList[i].Cells[1].InnerText.ToString();
}

Any advice/tips/feedback is appreciated for this newbie...

- Chris