As I noted before, as teachers of composition we are in the perfect situation to help students with LDs. One of the reasons for this is that most of the problems these students have are in the process of reading and writing. Because much of our teaching revolves around these kinds of processes, much of what you do already in your composition class will be of use to students with LDs; you probably already emphasize the importance of drafting and revising, vital steps for students who cannot produce a "quick and clean" final draft in one sitting. You might also consider giving your class various "process" due dates, which will help motivate a student who has trouble getting writing done on time.
Peer workshop and response are also probably important parts of your pedagogy. However, students with LD can become very uncomfortable with peer responding. Sometimes they have a difficult time with proofreading and revising their own drafts, much less their peers' drafts. In addition, they might feel bashful about sharing their own rough drafts, which might have many proofreading and coherence problems. You can encourage students with LD to go to a Writing Center consultant for help working through a peer draft, or to do a pre-workshop tutorial on their own drafts. Or, you might have these students bring the draft into a conference with you. One experienced LD teacher suggested that, if these strategies do not help curb the student's fear of peer workshops, you might allow this student to be absent on the day of the workshop, with no penalty, or set them up with a regular writing center tutorial.
It is very difficult for a writing teacher/GTA, who already has very limited time, to give one LD student a lot of extra time. It is important for you to realize that you are NOT watering down the content of your class -- you are simply accommodating different learning styles that are generally ignored in traditional classrooms. In fact, most of the accommodations you can make in your classroom will be beneficial to all types of learners. On the other hand, it is going to be such a benefit to students with LDs if you give them extra office-hour time to work on strategies. You might also make them aware of the Writing Center where they can get more one-on-one attention. Most of the suggestions for accommodation that I will include here and in Attachment 1 are ideas that any teacher can employ without making huge adjustments -- good practices for any effective teacher. Attachment 2, then, offers you ideas that you can pass on to your students and strategies that they can employ on their own.