Do either shredded pine bark mulch, pine nugget mulch, pine straw, or peat tie up soil N?

All of these products are usually used as mulch and not soil amendments. They will not lock up the nitrogen but in the process of decomposing they will use up a lot of existing nitrogen. It would be better if you used some sand (Not more than 1 part of 5) and used compost such as leaf mold or other non- manure compost to amend the soil. This will add slow release nitrogen as opposed to taking it away. From your description of the ph I would also use several hundred pounds of dolomitic limestone or 50 or so pounds of hydrated lime to bring the ph to a more neutral point.