I had the same problem getting the 2 Puny Carrots, with heightened economy. But I found them in the cabinet in Bowerstone Marketplace's pub. Second floor. It's random when they pop. Just go get the items there, then fast travel to Bowerstone Old Town - Market Road, then run back to Marketplace. The cabinets will have new items. Repeat until you get the carrots. I got them with 4 and 5 star economy.
As for the Murgo's Trading Books, I found them in the bookstore, on the shelves, a book trader walking around near Wraithmarsh I think, another from digging, and I believe I found a 4th in a treasure chest.
The Lutes can be bought all the time, in Oakvale... from the Gifts Trader, near the bar. But I believe only one can be bought at a time. So you'll have to leave, and possibly sleep 7 days for him to replenish his stock, then go buy another.