The card you have attached is the index card showing that the soldier's widow applied for, and received, widow's pension for Joshua's service. She also applied for bounty land under the act of 1850, which made some 1812 soldiers eligible for bounty land for the first time. Their widows and even their heirs could apply for it, and that is what Eliza did.
The bounty land application should be filed in as part of the pension file. Those 1812 pensions are being scanned and put online for free at the Fold3 site, however, it is slow going and they are not up to letter "F" yet.
You can go to the Bureau of Land Management website at
www.glorecords.blm.gov and click on "land patents" and scan for the soldier's name. A list of men with that name will come up. Look for the one that has Joshua with a "w" beside his name, and other people, including his wife, with a "p". If Eliza patented land, she will have the "p" (for "patentee), and there won't be any other names. If she sold the warrant to someone else, there will be another name besides hers with a "p" beside it. You can click on "document image" to see the patent certificate.
This soldier/widow would have a service record, a pension & bounty land file, and a surrendered warrant file at NARA DC. None of this is microfilmed or online yet. I can made color PDF scans for any or all of these files.