recently I bought some builder's ware and the whole file has disappeared from my inventory,

[gazelle Falconer]

has this happened with anyone else?  It was a fledgling file that was worth about $15.00.

[Nalates Urriah]

What is a fledgling file?

People have lost things from inventory. These days it is very rare. More often it is a connection problem and the list of what is in your inventory doesn't fully download to the viewer.

Having a good Internet connection does not mean you have a good connection to the SL servers.

So... visit an empty deserted region like Furball. Log off and then login at Last Location. Open inventory and search for anything in your inventory. See if the entire inventory will load and your item reappear.

Use search and filters to see if you can find it.

If all that fails, file a ticket with SL Support to see if they can find it.

You can test your connection the SL servers using this info: http://blog.nalates.net/2011/10/26/troubleshoot-your-sl-connection/