Is there anything you reccomend looking for when picking a tree?
David Benavente is a Spaniard Bonsai Artist and these are his recommendations:
1- Do not pay future at the price of the present (We should not have to pay for the tree that could be, but for what it is at that moment.)
2- Do not underestimate the risk of buying a weak or diseased plant (do not buy a plant in poor condition but if you do, the price should be so appealing that justifies the risk.)
3- Blessed are those who have found a reputable supplier (It is good to have a regular supplier, who over the years, have proven to be worthy of trust.)
4- A tree does not have to be more expensive because of being recovered (yamadori) (Sometimes trees that should not have been recovered by his lack of interest as a bonsai are charged with unjustified quantities of money only by the fact that they are yamadori.)
5- So, what is valued in prebonsai?
* Cultivation phase
* Phase of education of the rootball (nebari)
* Tapering of the trunk
* Texture of the bark and wood
* Proportion and movement
* Ramification
* Species
* Pottery
There is much more on his site, but it is in Spanish, that is why I dared to make an abstract from his much more extended advices in:
www.davidbenavente.com/?page_id=185
Hope I might have been of help