I had my roof replaced and the contractor initially covered by ridge vent and installed a number of turtle vents on the roof. I had them come back and install a ridge vent because they only shingled over gap in the ridge. Should I be concerned about the additional vents causing issues with the ridge vent? If yes how should I best cover up the additional vents? I have also seen some inexpensive carboard/plastic items that can be attached to the rafters to direct air flow to the ridge vent. Would adding these to my rafters help in reducing my energy expenses?

There should be no issues with the extra vents staying there. Ideally the more ventilation you have the better it is for the attic. Ideally the attic should be the same temp as the outside of the house.
Just be sure that your soffit vents are open and not blocked. These cardboard/plastic items are used to slightly compress the insulation to allow the vents to work properly. Adding these if the insulation blocks the free flow of air from the vents to the upper vents on the roof will help, some with energy but mostly with longer roof life and less ice damming during the winter months.

Berger Building Products has a product called AccuVent, http://www.bergerbros.com/BergerAccuVent.pdf , that looks like a better baffle than the usual polystyrene or cardboard baffles.

You can order them online at HomeDepot.com ... Search for "insulation baffle".

Those baffles are great to use in new construction, but almost impossible to install in old work. You simply cannot get into the area to fasten to the top plate. Also there were ideally designed for blown insulation to prevent it from falling into the soffit area.

"Those baffles are great to use in new construction, but almost impossible to install in old work. You simply cannot get into the area to fasten to the top plate. Also there were ideally designed for blown insulation to prevent it from falling into the soffit area."

Amen!!! Unfortunately for me no baffles were used when they blew in the attic insulation in my house. I'd say at least 90% of my soffit vents were totally blocked by cellulose insulation ... good excuse to buy a new shop vac! Fortunately I have a pretty steep roof (and I do yoga), so I have been able to get out to the edges and staple the baffles to the top plate.

Appreciate the replies, I can rest more easily and have some baffles to purchase and install.

we resently had a new roof installed. ice cap, felt paper and shingles and replaced ridge vent. we have a gable on each side of the house and a roof fan. we now have A ventilation problem. there is moisture and mold on the northeast side of the inside of the roof.the roofer feels it is a ventilation problem but no connection to the new ridge vent. it is winter and 30 some degrees. we don't know how to solve this problem

A ridge vent alone will not provide sufficient ventilation for your roof. Ideally, there would also be soffit vents with a net free area approximately equal to that of the ridge vent, with a clear air space above your insulation of at least 1 1/2 inches.

If all you have is the ridge vent, or even if you also have gable vents, the roof fan will be short-circuiting the air...in the vents and out through the fan without ventilating the lower portions of your roof. Also, if you have any leakáge through your insulation anywhere, the fan could be pulling moist heated air from your house. You need a low-lever air inlet, and if you had it, you probably would not need the fan at all.