I have discovered to my delight that you can integrate Lightroom and barcode based print asset management. This is a way to:

1. automate the printing of labels for images without any rekeying of information, and
2. automate the process of finding the image from which a print was made

Why do this? You may sell prints or just make them for your own pleasure. It is good practice to provide some labelling of prints so you (or the buyer) knows what they are looking at. It can be helpful to be able to quickly find the source image of a print. Of course you can just include the filename in the label and type it in to find the source image. But the labels produced look a bit messy with a sometimes arbitrary filename stuck in there. An option is to include a neat barcode on the label. You can then use your webcam to read the label and direclty insert the filename in the LR search field. Presto! Up pops the image from which the print was made.

Caveat: Apologies to Mac users, I have only worked this out on a PC. I’m sure there are substitutes for each of the things I’ve used.

What you need to do this [on a PC]:

• Lightroom (LOL) (BTW Jack Nack showed LR use way outpaces Aperture on the Mac – there is a reason guys – LR is better!)
• LR/Transporter (incredibly useful for many things)
• Excel (optional but part of my workflow)
• A way to print labels with barcodes. I use a cheap Brother label printer which comes with the P-Touch Editor software.
• A webcam
• Webcam barcode reader software. I use bcWebCam which is free

How I do it:

I’ll sketch how I do it with the specific gear I have and then suggest how you may get by with other gear.

Simplest workflow:

1. Set up LR/Transporter to export a summary file from image exports that includes all the fields you may want on your label (including filename of course). Format for  comma delimited a CSV file with a header line to define the exported fields. This is saved and reused as an export preset. Routlinely I can then select the images I am printing and export them to a dummy folder which I use for the purpose of transferring Image information.
2. I use my label printer software with a template that merges the CSV file data onto a label, with the filename printed as a QR barcode. I generally put one label directly on the print reverse and, if framed, another on the frame rear. With high quality art prints I only do the latter to avoid any possibility of problems of with the adhesive discolouring the paper obverse. Here’s an example:
   
3. Having previously installed bcWebCam, whenever I want to if I need to find an image that needs a bit of a search (only likely if I’ve not worked on it recently), I load bcWebCam while LR is running, place my mouse cursor in the search field in the library view (having selected the root of my catalogue), and hold the print label in front of the web cam. Presto! bcWebCam inserts the filename in the search field and up pops the image in LR!

In reality, I use excel as an intermediary to read the LR/Transporter data and reformat some items. Excel also lets me define how many of each label I want printed… The label printer software automatically reads the excel file as a database and allows printing of the required number of labels.

If you are interested in this solution you are likely to have tens or hundreds of thousands of images in which case camera generated filenames will not be unique. I add a month and year on import and conversion to DNG into LR to ensure filenames are unique. There are a range of other work-arounds that may suit your workflow better. But remember, you need something that LR will find in a single search. It may be you create a unique identifier in a EXIF or IPTC field – this will work too…  Some smart bunny may point out to me there is some foolproof automatic unique identifier for each image built into LR which can be accessed and exported but I am not aware of it. I guess image creation time (to the second) comes pretty close but I cannot see how to search on this from a search field entry…

Where you may need to find some workarounds:

If you are on a PC, the one thing that is not available on the net is the barcode label printer. In the past I used to print labels on multi-label sheets with a laser printer. It’s not obvious to me how to translate the unique image identifier into a barcode for this approach but I’m sure this will be one. But I came to the conclusion that a dedicated “on demand” label printer would save a huge amount of messing around. I think the Brother model I use is about US$79 (A$99) which doesn’t exactly break any bank. And the continuous paper roll I use means labels end up about 2.5 cents a pop…  What make this or even the more capable models (with auto-cutters) such a great deal is the P-touch sofware which does do all the linking of database to label and info field to barcode. This is worth the price alone I reckon. There are other free and for-fee webcam barcode readers out there too; the one I’ve noted works for me…

This may sound pretty complex to set up. But the reality is, once export, database and print templates are in place, it’s all automatic.